how to write a children's book

AJ Cosmo is the bestselling author of The Monster that Ate My Socks and more than 20 other fun children’s picture books. His stories are crafted to help parents teach children lessons in a fun and engaging way.

Six years ago, AJ was at his day job searching for ways to make money online. One of the ideas in a writer’s forum was to write books and put them up on Kindle because, as the poster said, “Kindle is a gold mine!”

The group of writers AJ eventually joined were publishing two types of content: adult fiction, and children’s books.

Some years ago, AJ moved out to Hollywood to try his hand at being a screenwriter. The first books he tried to publish and sell on Amazon were adapted from screenplays. When he got the suggestion to try publishing children’s books, it interested him because it was something he felt he had a talent for, because he’s able to draw and be a little goofy.

AJ wasn’t interested in writing adult content.

When AJ wrote his first children’s book, he didn’t know anything about the different grade levels or reader expectations. He just wanted to tell a funny story and do some illustrations. It took three or four books before AJ saw any kind of return on investment with his writing.

His fourth book was The Monster that Ate My Socks. That book took off and allowed AJ to make a career from publishing children’s books on Kindle.

It took off on its own, and ever since then AJ has been trying to reverse-engineer its success.

Six years later, AJ has published more than 40 books. And he’s doing this full time to earn a living.

The Success of The Monster that Ate My Socks

AJ still doesn’t understand exactly why The Monster that Ate My Socks became such a huge success.

One thing that contributed to its success, as far as AJ can tell, is that it’s short. The book is about 3,000 words, and 20 pages in print.

The book has six illustrations. There isn’t a magic number when it comes to the number of illustrations in a children’s picture book—you use the number you need to get the story across.

In fact, the book actually goes against the traditional wisdom regarding the number of images you need in a children’s picture book.

The Monster that Ate My Socks is technically a chapter book, but it’s much lengthier than a typical chapter book for very young children…and yet the language is much simpler than books published for middle-grade readers.

The book carved out its own little niche in the children’s book world. If AJ had known the rules of writing children’s books, he never would have written The Monster that Ate My Socks.

Parents have told AJ that besides being entertaining and funny, the book actually solved the monster problem for them with their kids. It humanized monsters, and allowed children to relate to them so they were no longer afraid of turning off the bedroom light and going to sleep.

how to sell children's books

Marketing Considerations for Children’s Books

“Children’s books [like nonfiction books] can have meaning and purpose beyond just entertainment.”
– AJ Cosmo

“When you’re selling children’s books, you’re not actually selling to children—you’re selling to the avatars of children: their parents or their teachers. You have to communicate something to the parents, that your book is beyond mindless entertainment.” – AJ Cosmo

Parents expect a children’s book to be entertaining by default. What they want to know is, beyond entertainment, what can this book do for them or their children?

There are thousands of children’s books published every year. So in order to differentiate your children’s book from other books for children, you have to consider what lesson your book can teach your audience.

You have to walk a fine line. If your lesson is too serious, your target audience will zone out and their parents won’t buy your next book. But if it’s got too little lesson in it, the parents won’t think it’s valuable enough to buy your next book, either.

The lesson your book teaches is a marketing point. It’s something you have to consider, but always remember the age of the audience you’re aiming your book at.

There’s nothing wrong with creating a book that’s entertaining. There’s nothing wrong with creating a book that specifically designed to make children laugh. AJ is currently working on The Giggle Game, a book designed to do exactly that.

But even The Giggle Game has a point to it. The book is designed as a wind-down game for children before they go to bed. Giving your books a reason to exist beyond entertainment is a major selling point in the children’s book marketplace.

What’s Your Book’s Purpose?

This lesson can be extended to other genres of fiction. If you’re writing a romance novel, what is the extra that the audience is getting besides the romance? Are you showing them an exotic location? Are you showing them a situation they’ve never seen before?

“What are all the aspects you can have to sell your book? How can you communicate that?”
– AJ Cosmo

How to Test a Children’s Book in the Market

Testing ideas in the marketplace is smart, because it helps you see if your book has the potential to sell well.

So how do you test a children’s book?

  • You ask other parents.
  • You get your book in front of children and get their reaction.

If you want to be a children’s book author, it’s very important to actually read the books to children and gauge their reaction.

Kids are the best critics in the world because they’re honest. If your book isn’t holding their attention, they will wander off and go find something to play with.

Meanwhile, you want parents to like reading your book as much as children like it. AJ has heard of several books that parents hide from their children because they’re tired of reading the book to them so often.

Children are learning pattern recognition. Their learning to predict things that will happen. That’s why they want books read to them multiple times.

  • Ask other writers of children’s books. A lot of people think writing a children’s book is an easy thing to do.

It’s really not. AJ has revised some of his children’s books more than he’s revised his novels.

Don’t assume writing a children’s book is going to be easy.

How to Do Illustrations for Your Children’s Book

Illustration can make or break a book. You need to make sure your illustrations are of good quality.

“Your illustration needs to be up to par based on the expectation of what a good illustration for children’s book is. That is a huge range.”
– AJ Cosmo

When you go to illustrate a book, figure out what your budget is to hire an artist, then see how many books you would have to sell in order to recoup that cost. It’s a simple business calculation, and you have to factor it in if you want to make writing children’s books a business.

It’s important to live up to the expectations that the audience has.

Tips for Collaborating with Your Illustrator

  • It’s important to understand what you have, and what you want from the end product.
  • Do you have comparable books? This is something every author should be checking out no matter what type of book they’re writing. Find books like yours and analyze them to see what elements you can incorporate into your books.
  • Once you find comparable books, give those books to the artist so they have an idea of what type of illustrations you want.
  • Give hard deadlines to your artist.
  • Try not to micromanage your artist. Micromanaging will drive everyone crazy.
  • Break up your payments to be delivered over the life of the project.
  • Check on your artist. But give them enough freedom that they enjoy the process of helping you create your book.
  • By giving the illustrator artistic freedom within guidelines, you’re going to get the best product possible, and possibly far below market rate.

How Do You Publish a Children’s Book?

Formatting is one of the biggest challenges when it comes to publishing children’s books, because you’re publishing to a split audience.

Some people have original black-and-white Kindles, or the Kindle Oasis. Those devices don’t support rich formatting. They only support basic pages that allow for static images with text.

Kindle Fire models, as well as the Kindle apps for iPads and smartphones, allow you to do much more dynamic formatting.

On top of that, the aspect ratio for a children’s ebook is different than a print book. So you have to take that into consideration.

You sometimes have to make multiple versions of the same image to make sure that your book works on multiple devices.

You can make CreateSpace perfect-bound soft covers if you want to put your children’s book into print. The problem with that is, if your book is a short picture book, you end up publishing what looks like a pamphlet.

You can do hardbound books with crisp full-color illustrations through Ingram Spark. The problem with Ingram Spark books is that you only make about $0.50 per book sold for a short, full-color children’s book.

There are a lot of options when it comes to getting your children’s books out in the marketplace. The challenge for indie children’s book authors is that they have to create a different edition for each one of the distribution methods. It’s a lot more challenging to do a children’s book in terms of formatting than it is to write a novel.

If you don’t know what you’re doing, definitely get professional help with the formatting. It’ll be worth your investment.

Make sure whatever version of your book you’re working on works for whatever type of book you’re formatting for.

How AJ Promotes His Children’s Books

AJ has a fan club of readers within his email list, and he’ll send his book to them first. He’ll send a free copy of his book to his fans before the book is live on Amazon. He’ll also send a note asking them to please give their honest opinion of the book on release day, and if they wouldn’t mind posting about it on social media, that would also help.

Having good word of mouth is the best thing you can do to boost your book sales, and having an early review crew is the best way to get early word of mouth going.

For the last book AJ published, he had a review crew of 35 people. You should always seek out twice the number of reviewers as you want reviews on launch day. Only half the people you ask to review the book will actually review the book by launch day.

Don’t try to control your results beyond that.

There are several different things you can do to promote your book. You can:


  • Give away a gift card.
  • Give away a print copy of your book.
  • Dedicate your book to your early review team by name.
  • Do anything else you can think of that might cause people to show interest in reviewing your book.

Send a reminder email when you send the book out, and then remind them on the day of the launch.

That’s how you successfully build an early review team, and get reviews for your books on launch day.

Make your marketing as organic as possible. When you first release your book, talk about how people are receiving the book on your social media platforms.

Share Your Progress

Be sure to show a lot of gratitude. Showing the process of creating the book, especially with children books, can be a great way to build buzz for your book before it’s released.

Showing your audience your process is a very organic way to market your book. It also gives them things that they will want to share. Creating a children’s book is a very cool thing, and it’s interesting to lots of people.

Sharing your process allows you to talk about something you’re excited about in a genuine and authentic way that doesn’t seem salesy.

Get Feedback

The other thing you can do is ask for feedback, even if you’re not going to incorporate it into the finished product. What you learn may inform future projects, and any way your audience can feel like they were part of creating the book will give them an investment in your success going forward.

People who have contributed to the final version of the book are more likely to buy a copy on launch day, and they’re more likely to tell their friends about it.

Try Amazon Ads

You can also buy Amazon ads. When you do Amazon ads, you have to know what your comparable titles are. Who are the authors in your genre people know that have books like yours?

Knowing your comparable titles will influence:

  • What your cover looks like.
  • What your product description sounds like.
  • Where and how you advertise your book.
  • Your ad copy.

Be consistent. Share things on Facebook and your other social media channels, but don’t be annoying. The last thing anyone wants to see is an advertisement on their social media.

Make your marketing organic. Make it as disguised as possible. And make it about yourself.

How to Market Children’s Books Offline

Offline marketing is also critical for selling children’s books.

  • Talk to other authors.
  • Tell people in person what you’re doing.
  • Make yourself known.
  • In general, say yes to everything.
  • Help other authors before you ask for help.
  • Any kind of help you can give people will want to reciprocate most of the time.
  • Network with other author friends and see if you can split the cost of some book fairs.

Links and Resources Mentioned in This Interview

The Monster that Ate My Socks – AJ’s bestselling children’s book – AJ’s website  – AJ’s publishing company  – Chris McCullen’s Kindle Kids Creator how-to   – AJ’s SCBWI article on fixed format vs. fluid for kids’ books – the Society of Children Book Writers and Illustrators. You can join this organization to get yourself known within the children’s book community.

Use IngramSpark to publish your children’s book in hardcover.

AJ Cosmo’s Amazon author page