This guide is also available in Spanish.

In 2016, I read 57 books. I read like I was running out of time.

It felt like an achievement, yet by the end of the year, I could scarcely recall even one useful idea from each book.

That moment was a turning point. I realized very little of the information I was consuming was sticking.

Taking notes on the books I read was a great start, but it wasn’t enough. It did me no good to leave those notes sitting in a software program like a musty filing cabinet in the basement, never to see the light of day again.

I realized if I wanted to benefit from my reading, I needed to engage with the books I read on a much deeper level. I needed to make something out of them. Otherwise, I would continue to passively consume information with no lasting memory of what I learned.

I decided to slow down, carefully choose a much smaller number of books, and save my notes from those books in a system of knowledge management – which I call my “Second Brain.” I decided I would rather deeply absorb the wisdom of a small handful of books than speed-read my way through dozens.

The 20 book summaries I’ve created since then have changed the trajectory of my business and my work. They have attracted hundreds of thousands of page views over the last few years.

Creating a book summary requires a surprising amount of creativity. Because the truth is, these are much more than summaries. They are actually reinterpretations. By choosing certain points over others and deciding how they’ll be presented, I am interpreting the book through my own personal lens.

Instead of apologizing for this, I encourage you to embrace it. Like any retelling, your summary is biased, but it can be biased helpfully. It can be biased toward usefulness, toward relevance, and toward actionability.

Blog posts are not miniature books. When you change the length, the whole nature of the text changes. 

A book might build up slowly using stories before getting to the punchline, while a blog post demands that you lead with the main argument. A book might include personal anecdotes from the author, whereas blog post summaries have to be more direct and utilitarian. Books keep revisiting the same points again and again from different angles, whereas a blog post only needs to address each point once.

Authors have to write for the largest possible audience – for the widest range of educational levels, cultural contexts, and common knowledge. They have to assume that their readers know little or nothing about the topic, which is why so many books feel like “a book that should have been a blog post.” The economics of the publishing industry demand mainstream success.

But you are not similarly constrained. You have a particular audience, and you know that audience. You know what they tend to miss, what they need, and what they desire in their heart of hearts. You can therefore afford to be FAR more discerning and opinionated.

In fact, I think you owe it to your readers to be opinionated. They rely on you to tell them what matters about the book – which points are the most original and important. They depend on you to climb the mountain and come back with the most precious gems. You have done the hard work, and now you are paving the way for others to follow in your footsteps.

This isn’t an easy process. Each summary requires 10-20 hours of intellectual labor. But looking back at the last few years, these hours have been some of the most valuable I’ve spent toward building an audience of loyal readers, and ultimately creating the content and courses that fuel my business.

In this article, I will share with you the profound benefits I’ve experienced from summarizing books, what I’ve learned from the experience, and the process I’ve developed to do it as efficiently as possible.

Let’s dive into each of the benefits of summarizing books, in roughly the order they appear:

  1. Allows me to absorb the book’s lessons on a much deeper level
  2. Creates building blocks for my own thinking and creating
  3. Improves my writing through imitation
  4. Builds my audience of email subscribers
  5. Connects me with influential people
  6. Expands my visibility and credibility in online communities

1. Allows me to absorb the book’s lessons on a much deeper level

Summarizing a book is a far deeper level of engagement than passive reading.

The moment I decide to summarize a book, it’s as if my vision suddenly sharpens. I begin to pay closer attention and read with a more critical eye. I’m less willing to give the author the benefit of the doubt. I start to question their statements and conclusions and to examine the supporting evidence.

As I decide what to highlight, which is the very first step of summarizing, I’m practicing my judgment – the skill of deciding what matters and what doesn’t, what’s important and what’s not, and what’s interesting and what isn’t. I’m training my ability to notice what is most relevant and valuable.

When I summarized The Complete Guide to Landing a Book Deal, for example, it gave me tremendous clarity about the book proposal I was writing at the time. There was so much advice about what to do and what not to do, but it was only when I wrote it out in my own words that I fully absorbed it. Once I did, it was far easier to see which pieces of conventional wisdom I wanted to follow, and which I wanted to disregard.

Summarizing a book requires you to make value judgments at every stage of the process. This forces you to think about the material more deeply and reflect on how you want this new wisdom to be applied to your life.

It would be worth summarizing books even if deeper learning was the only benefit. But it is only the beginning.

2. Creates building blocks for my own thinking and creating

Once I started engaging with books more deeply, I began to notice something: the knowledge I gained from them served as building blocks for my own thinking and creating.

This doesn’t really happen with books that I casually read. I might have a vague idea of how my ideas are connected to something I read a long time ago, but without the summary, retrieving it is too much effort.

I’ve found that with the best ideas from books summarized on my blog, I can directly link to them as specific, concrete sources. I can write something like “As discussed in Emergent Strategy…” and link to my own summary, instead of to an Amazon page and expecting my readers to somehow read an entire book to understand what I’m talking about.

That link leads to another place inside the world of ideas I’m creating. It points to an article written by me, in my own language, with my own framing. I don’t have to interrupt what I’m writing to explain all the backstory, nor do I have to leave my readers behind.

This is how my blog becomes more than the sum of its parts – my posts make up an interconnected web of thinking that others can follow in any direction and read in any order. I can build one idea atop another, which allows me to take my readers along on my journey knowing they can trace my footsteps. Sharing that common knowledge, I’m able to move further and faster in my thinking without having to stop and explain the background again and again.

This way of thinking is less like a passive consumer and more like a researcher. You have a body of research that you are growing and refining over time. You have hypotheses and questions that, if answered, will lead you closer to your research goal. And you are part of a network of collaborators constantly sharing their thinking and building atop one another’s work.

Your book summaries are the building blocks in the edifice of understanding you are constructing.

3. Improves my thinking and writing through imitation

Eventually I noticed something else: When I summarized a book, I inhabited the author’s state of mind.

While summarizing How Emotions Are Made, I started to see people’s emotions through the eyes of a neuroscientist. While summarizing The World Beyond Your Head I suddenly became hyper-aware of how every little distraction was affecting me.

I even noticed that I would start writing and speaking like the author. 10 to 20 hours is a significant amount of time to spend with someone’s thinking. It is more like doing an apprenticeship or taking a class than reading a book.

A classic piece of writing advice is to copy out the writing of your favorite authors, by hand and word for word. This is the writer’s equivalent of imitating an athlete’s movements or a musician’s signature style.

I see summarizing books in the same vein: By imitating the thought patterns and language of the person whose work you are summarizing, you get to inhabit the mind of a master. But it is even better than pure imitation: You are riffing on their words, weaving them in and out of your own explanations.

One of the most wonderful moments is when I encounter the same challenge or obstacle in trying to explain something that the original author encountered. I recognize what they were trying to do and how they thought through their options. Seeing how they ultimately overcame those obstacles provides a far deeper level of insight than only seeing the final result.

And once in a while, I even find a way to explain certain ideas better than they did. It’s like a long-distance collaboration they don’t even know we’re engaged in.

4. Builds my audience of email subscribers

As powerful as email can be as a communications medium, there are significant barriers to getting people to subscribe. They already receive way too many emails and can’t even consume the content they already have. What does yours have to offer that’s too good to miss?

Summarizing books is an excellent way to get on people’s radar. Because they often already have an intention to read one of these books, seeing a summary feels like a timesaver when compared to the time required to read the whole book.

I am tapping into the existing reputation of a book and its author and curating its best ideas for the many people who are too busy to read it themselves. Instead of asking them to do me a favor (Hey, please read my post!) it feels like I am doing them a favor (Hey, here’s a 15-minute summary instead of a five-hour book!).

For example, the book Supersizing the Mind: The Science of Cognitive Extension (members-only) was one of the most fascinating, but also most grueling books I’ve ever read. It is written like an academic paper, with countless technical explanations, overly detailed examples, and bunny trails into related topics. I knew that the ideas contained within it were critically important for anyone working in the field of knowledge management, but I knew that very few would be able to spend the nearly 20 hours it took me to get through it.

Now I have a concise summary of the book that I can send to a startup founder, software developer, or teacher who can benefit from the most recent advances in the field.

All this boils down to one fact: When you save people time, they are grateful. They want to hear more from you. That’s why they subscribe, tell their friends to subscribe, and share your links on social media – because you provided value upfront.

5. Connects me with influential people

Eventually, I started to gain enough of a public profile that I could reach out to the authors themselves.

Put yourself in the author’s shoes: You’ve published a great book. People have heard of you. Everyone wants to talk to you. How do you prioritize how you spend your time publicizing your book?

You are obviously going to prioritize the people who already invested their time to make your work more accessible to others. You’re going to favor those who have taken the trouble to broadcast your ideas to their own audience.

After publishing my summary of How To Take Smart Notes, I reached out to the author, Sönke Ahrens, and he agreed to a Q&A with my audience. A couple hundred people attended the live call, and the recording has now been watched more than 10 thousand times on YouTube. My book summary ranks higher on Google than the book’s own website!

Make no mistake: Over time, these kinds of relationships can have a dramatic impact on your career, your business, and your life. These are people you can’t buy access to. They won’t be bribed or flattered. They are people who care about ideas, and the path to their heart is only through ideas.

Just remember that they don’t owe you anything, and you shouldn’t expect anything. Making contact should be considered an extra bonus, since you never know who will be open to connecting.

But if they do respond, these can be incredibly fruitful collaborations for both parties.

6. Expands my visibility and credibility in online communities

An unexpected side effect of writing these book summaries has been the exposure they’ve given me to existing online communities.

The number of communities you can meaningfully participate in will always be severely limited because there are so many. You can’t be everywhere at once, nor should you try.

However, book summaries are unique in their ability to slip into conversations. Because they focus on providing value instead of self-promotion, most community moderators will allow them to be shared. Often, they will be grateful to you for providing a valuable conversation starter, since they are always preoccupied with keeping the community engaged.

Communities are likely to already know about books in their niche, so they’re primed to receive them. Several existing personal finance groups loved reading my summary of the book You Need a Budget. Sometimes, people with large followings or even the original author themselves will share your summary with their audiences, which is a personal introduction to thousands of eager readers.

Summarizing a book and sharing it with a group of people who have already signaled their interest in it is the opposite of spam. It is a generous, honest, and helpful way of contributing to the knowledge of others.

Those people are far more likely to follow you, subscribe to your services, and give you helpful feedback on your work.

How I Decide Which Books to Summarize

Notice that none of the books I’ve summarized are mega-bestsellers. There would be no point to that, because bestsellers are already well known. They are often available in many formats and summaries already exist online.

Instead of bestsellers, I look for books that are on the fringes of the topics I care about. Ones that my followers aren’t likely to see if it wasn’t for my summary. I look for subjects where I can move the needle, connecting topics or ideas or groups of people that are likely to have answers to each others’ questions.

In my summary of The Body Keeps the Score, for example, I was curious about how recent advances in our understanding of trauma might shed some light on people’s struggles with focus and commitment. I had listened to an interview with Dr. Gabor Maté on the Tim Ferriss podcast and was fascinated when he linked misdiagnosed ADHD to childhood trauma. I wanted to not only explore that connection for myself, but to build a bridge between Dr. Bessel van der Kolk’s work and the productivity world where many struggle with attention deficit.

When I summarized adrienne maree brown’s book Pleasure Activism, I wanted to better understand the relationship between productivity and enjoyment. I had noticed that the most effective people profoundly enjoy the work they do, and I wanted to expose my readers to brown’s unashamed embrace of pleasure as an organizing principle.

As a third example, I summarized my favorite ideas from the book Trekonomics, a fun exploration of the economics of the fictional Star Trek universe. In that universe, any product can be fabricated for free, which means the writers had to invent a completely new kind of society not based on the scarcity of goods. I had noticed a common theme across my work dealt with moving from a mindset of scarcity to a mindset of abundance, so I wanted to understand what a post-scarcity world might look like in our own time.

I want to be clear: The process I’m about to describe is NOT for every book you read. As a 10-20 hour endeavor, it should be reserved only for the most important, impactful, life-changing books you encounter. Think of it as the high-pressure power-washing of reading, reserved only for the most extreme jobs.

Generally, I read books that meet as many of these three criteria as possible:

  1. They are interesting and captivate my attention
  2. They are unique and have something original to say
  3. They are helpful in addressing the problems that my readers and I are facing

The books I summarize have to meet an even higher bar. They have to be so interesting, so unique, and so helpful that the time I put into summarizing them will actually save me time in the long run. In other words, books that are such foundational building blocks in my work that by investing the time upfront to summarize them, I’m saving my future self the time of having to explain them over and over.

When you put in the effort to summarize an entire book, you are building a bridge from your audience to a topic they’re unlikely to read about on their own. You are lowering the threshold for how much time someone needs to spend to access its ideas, from hours to minutes.

Bridge-building isn’t easy, but it’s more important than ever. We’re all descending deeper and deeper into our filter bubbles as the algorithms feed us only what we already believe. It seems to be getting harder to discover points of view outside our own. We need ambassadors and translators who are willing to do the work of introducing us to foreign ideas we might never encounter on our own.

Step-by-step guidelines for writing your summary

If you’re still reading, you probably have some interest in trying book summarization for yourself. So how do you do it? It’s time for the practical instructions, which I’ve demonstrated with guided videos below.

I follow five steps to go from reading a book to publishing a summary blog post:

  1. Read and highlight
  2. Export highlights
  3. Progressively summarize
  4. Outline
  5. Write

Step 1: Read and highlight

The first step is to read the book. Most books take five to ten hours to read, which is the single largest investment of time you’ll make. So you want to avoid having to repeat this step more than once.

To enable you to read straight through the book in one pass, you’ll combine reading with highlighting. Highlighting by itself has been shown to be of “low utility” in learning, but in my opinion these findings completely miss the point. Highlighting is not supposed to be an end in itself. It is just the starting point in a much longer process.

Other studies have shown that highlighting results in deeper thinking and better retention. Yue et al say (emphasis mine):

…questioning during highlighting and re-reading should evoke two beneficial activities for

improved retention: deeper processing and retrieval practice, both of which have been repeatedly shown to improve retention (e.g., Craik and Lockhart 1972; Roediger and Karpicke 2006)…it is not highlighting per se that is beneficial; rather, it is how highlighting changes the way students read and think about text that is beneficial.

That last phrase is key: Highlighting is one essential link in a chain of deep engagement with a text. It allows you to read efficiently without constant interruption. It takes barely a few extra seconds to highlight a word or phrase that you’re already reading anyway.

The ease of digital highlighting is the main reason I recommend ebooks. There is something special about paper books, and ebooks have their fair share of flaws. But highlighting is one aspect of ebooks that is far superior: You simply put down your finger, swipe across the text you want to keep, and the text is highlighted.

My preferred platform is Amazon Kindle, because I’ve found the highlighting and export to be very reliable. I also occasionally use Apple Books for ebooks from other sources.

In the 18-minute video below, I demonstrate what ebook highlighting looks like on the Kindle app for iPad as I read the book Work Clean: The Life-Changing Power of Mise-En-Place to Organize Your Life, Work, and Mind (affiliate link):

Watch on YouTube: How to Decide What to Highlight in Ebooks

As I read, I’m constantly asking myself the same three questions that I used to decide what to read in the first place:

  • Is it unique?
  • Is it helpful?
  • Is it interesting?

These questions serve as a threefold lens allowing me to focus only on the content that is most valuable.

If it’s not unique – something I haven’t heard before or that I’m surprised by – then what’s the point of repeating it? Most content in most books is common knowledge that you can skip over.

If it’s not helpful – a piece of information that equips people with solutions to their problems – then it’s fluff. By compressing a book into only its most actionable, relevant points, you do your readers a great service.

If it’s not interesting – a surprising or insightful idea that catches people’s attention – then it will only dilute the emphasis on the points that are interesting. It doesn’t matter how useful your writing is if it can’t hold people’s attention.

These guidelines might seem straightforward, but it takes practice to apply them consistently. As you read, it’s tempting to indiscriminately highlight an entire paragraph (or page) with a vague notion of “I’m sure something in here is interesting.”

But I encourage you to take an extra moment to ask yourself, “What exactly in this paragraph or page is worth keeping?” Those extra moments of consideration on the front end will save you hours later on.

Here are other helpful highlighting guidelines I’ve discovered over the years:

Do’s:

  • Do highlight chapter titles and section headings – this ensures your exported notes will preserve the structure of the book.
  • Do highlight lists and summaries already found within the book – this is valuable summarizing work the author has already done for you.
  • Do highlight “popular highlights” (a feature of some ebook services such as Kindle which shows you phrases that many other people have highlighted) – these are phrases that other readers have already told you are helpful in their understanding of the text.

Don’ts:

  • Don’t highlight entire paragraphs or pages – this will create a lot of work later on to figure out what is actually valuable in those large chunks of text.
  • Don’t highlight entire stories or long examples – they are usually too long, and you can always go back and find them if you need them.
  • Don’t highlight ideas or explanations that you already know, agree with, or could have guessed – focus on what is novel, surprising, and counterintuitive.

2. Export highlights

Highlighting is an important first step, reducing the amount of content you’re dealing with by at least 90% (since most ebooks don’t allow you to export more than 10% of the text anyway).

But those highlights do no good sitting in your e-reader. To remix them into something new, you have to take them out of their original context and bring them into an environment you control.

That environment is a digital notes app. I use the popular notes app Evernote (affiliate link), but you can use a wide variety of similar apps like Microsoft OneNote, Bear, Notion, or Roam Research. The important thing is that you have control over the content and can edit it in any way you please.

But first, we have to get our highlights out of the book and into our notes. In the video below, I walk through how to do this for a Kindle ebook using a free tool (Bookcision) and a paid service (Readwise):

Watch on YouTube: How to Export Ebook Highlights to Your Digital Notes

It might feel strange to remove your highlights from their original context and dump them all into a single note. But it’s important to remember that you’re not losing all that context. You’re hiding it just out of sight, so you can focus on the most important ideas.

You can always go back and revisit the original book for any reason, and it only takes minutes. This is another reason I prefer Kindle, because I can open the Kindle app right on my computer and see all my synced highlights, regardless of which device I originally made them on.

3. Progressively summarize

Now that you have a collection of passages you’ve decided are valuable, it’s time to compress them even further into the best of the best content. This is the purpose of my Progressive Summarization method.

Here’s the main idea: Every passage you’ve highlighted and exported has a point. But there are two problems:

  1. It’s not always clear what the main point is
  2. You need some of the surrounding context to understand what the point means

Progressive Summarization solves both problems at once by getting closer and closer to the main point in multiple passes, in a clearly marked way that shows you the necessary context around it. And it does this in the flow of reading so you don’t get interrupted.

Here’s what it looks like:

Watch on YouTube: How to Progressively Summarize a Digital Note

Here’s the wonderful thing about Progressive Summarization: Not only can it be done a little bit at a time over long periods of time — that’s how it should be done.

No one has time to sit down and do multiple passes on the same text all at once. And even if you do, I often find this results in worse summaries, since you can’t see the text objectively after looking at it for so long.

You can and should do one pass at a time, and the text will be waiting for you whenever you get back around to it. I’ve found that the more time goes by between passes, the more objective I can be about what’s truly worth keeping.

Below is a typical timeline for my summary of the book How to Take Smart Notes. I never made it a top priority, never pushed other projects aside to make room for it, and set no deadline for myself.

I ended up spending about 18 hours on the entire process, spread out over seven months. That comes out to only about 45 minutes per week on average. Like the other dozen or so Kindle ebooks I typically have active at any given time, I made progress on it whenever I felt like it and had some extra time.

After you’ve progressively summarized your notes, you’ve gone from 10% of the book to around 1%. That 1% makes up the richest, most insight-dense, most interesting and unique material. It is the core of insight around which the rest of the book revolves.

Instead of losing those nuggets in a sea of examples and explanations, you’ll make them the central pillars of your summary.

4. Outline

The fourth step is when your creativity and voice come to the forefront.

Until now, you’ve worked exclusively with a text that someone else has written. You identified and extracted the best ideas, but now it’s time to rearrange them. This requires a lot more decision-making.

Now is the time to distinguish between ideas that are great versus those that are merely good. Consider questions such as: Which ideas do I want to attach my reputation to? Which ones are worth hours of writing, rewriting, and broadcasting to the world? Which arguments or explanations can my summary improve upon?

What makes it possible to answer these questions is your previous work to compress the book into a small number of insightful nuggets. You can’t make an outline out of huge blocks of text. Bullet points demand conciseness.

In the video below I demonstrate how to use the layers of summarization you applied in the previous step to quickly jump from one main point to the next, so you can pull them into your own outline:

Watch on YouTube: How to Create an Outline with Digital Notes

The outline should be hierarchical, which reflects the hierarchical structure that your final summary will follow:

  • Main point
    • Supporting point
    • Supporting point
    • Supporting point
  • Main point
    • Supporting point
    • Supporting point
    • Supporting point
  • Main point
    • Etc.

This structure allows your eye to skip quickly from one main point to another to see if they make sense and are in the right order. And if you want to zoom in on any main point, you only have to move your eyes down and to the right.

Outlining is the only step that I strongly recommend you sit down and complete in one sitting. We’ve postponed it for as long as possible, but at this stage it is necessary to load all the main points into your head all at once. Only then can you compare and contrast and interconnect them into one structure in your mind. To avoid having to do that more than once, it’s a good idea to create the outline in one sitting.

5. Write

Now it’s time for the final step: actually writing the summary.

If you’ve done the previous steps, this is also in some ways the easiest part. You’ve already done all the thinking and decision-making required. You’ve decided which parts are the most important, emphasized the most important passages in multiple layers, and put them in an order that makes sense to you.

The final step involves stringing together the pearls of wisdom you’ve painstakingly selected into a beautiful necklace of reason. Because you have all the context you’ll need saved in your notes, you can spread out the writing process over time. If you get interrupted or have to step away for days or even weeks, your notes allow you to pick up right where you left off.

At this stage, all the difficult conceptual and strategic questions have already been decided. Which means I get to focus all my attention on writing – which language to use, metaphors and examples, not being redundant, challenging existing assumptions, etc. The flow is palpable and intoxicating, because I never have to stop to go look something up. I’m not afflicted with FOMO if I have to take out some material, because I can save it in my notes and use it elsewhere.

In this final video, I walk through writing my summary in my own words:

Watch on YouTube: How to Write a Book Summary

Here are my guidelines for the final stage of writing book summaries.

Customize your language to your own audience

You can be more specific and concrete with your words than the original book because you are writing for a much smaller and more focused audience. Use terms that they’ll recognize and relate to.

Leave out parts that are boring, obvious, or too long

Every word in your summary dilutes the emphasis on everything else, so don’t be afraid to leave out even entire chapters if they don’t add value. You are not writing a comprehensive, authoritative summary – you are writing a curated, abridged version of only the parts you find relevant.

Be selective with your examples and metaphors

Examples are important but usually quite long, so be very selective with the ones you include. Even better, add your own examples and metaphors of how you’ve seen the ideas play out in your own work and life.

Don’t include direct quotes unless absolutely necessary

I’ve found that using too many direct quotes interrupts the flow of reading, and turns your writing into a review rather than a summary. Instead, it is far more powerful to fully translate the author’s words into your own. A few short quotes are fine, but keep them to a minimum.

The power of curation

We are living in the midst of an “Infodemic” – a term coined by the World Health Organization as “an excessive amount of information about a problem, which makes it difficult to identify a solution.” Not only in health but in all areas of life, we are drowning in far too much information for any normal person to make sense of.

We all have to become curators of the information we consume. Curation has evolved from a specialized profession to a simple matter of staying informed about your field. But in curating information for ourselves, we also have the opportunity to surface the knowledge we’ve gained for others.

By taking the time to curate and summarize the work of others, you can offer people a way to access ideas they wouldn’t have the time to research themselves. You can lower the bar for how much effort it takes to engage with a new idea, in a way that informs while also being entertaining. More than ever, we need curators who are willing to distill what they know to just the essentials and then deliver that knowledge in engaging and understandable ways.

The work of curators isn’t easy, but that’s why it’s valuable. It requires sensitivity, creativity, and courage. As a curator, your reputation is on the line, which is what makes it a creative act within itself. But we have to go beyond just sharing a link and adding a clever quip. That’s what we do on social media, and it leads to misunderstanding more often than understanding. We need to add an extra layer of value: the context and perspective that comes from deeply engaging with new ideas.

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