Characters are at the heart of any story. If readers cannot connect with your characters, they won't care about the story, no matter how creative or exciting it is.
In a novel, the author can spend pages and pages describing a character's personality, background, motivations, hopes and dreams. In a picture book, words are few and precious, so the pictures need to do a lot of the work, showing both the visible and invisible.
That's not to say your character should be an open book. A character can have secret thoughts and hopes and dreams, but you the artist should know what they are. You should know everything about your character. This is difficult when you are not the author, but as illustrator you are co-creator of the characters and can impart your own ideas and personality into them.
Your art style will have a huge effect on your character design, whether your work is realistic, cartoonish, painterly, etc. But try to consider them as separate problems. Even within the realm of your style, there are hundreds of variations on whether a character is tall, short, has a big head or pointy chin or beady eyes.
The good news and the bad news is that there are no "rules" about what makes a visually appealing character. We know it when we see it. And even when you've been doing it a while, it's still hard work. But here are a few tips for designing great picture book characters.
1. Keep an open mind, don't rely on the kind of characters you always draw. Think of how you can push your characters further.
2. Consider the internal and external aspects of a character, which don't necessarily need to match. You might have a beautiful villain or an ugly hero, as long as they fit the story.
3. Simplify. Look for simple shapes and lines that can lend an abstract elegance to your characters.
4. Think about what physical actions the character needs to do – run? Jump? Sit in one place? Just as a cheetah and a hummingbird are built for what they need to do, so can your character be designed for a purpose.
5. Make a LOT of drawings of your characters, in all kinds of poses. Each time you draw them, you'll have a stronger understanding of their physical structure and they will become stronger.
6. Try giving your character some unique feature or trait or piece of clothing, so he or she will stand out from the crowd.
7. Try exaggeration of certain features, bigger or smaller.
8. Try drawing in a different medium than usual, to give your brain a different outlook on the character. Even if you won't be illustrating the book that way, it might give you a visual idea that you wouldn't have thought of.
9. Look at real people and animals for inspiration, not only for visual appearance but for how they move.
10. Trust your instincts and listen to your characters – when they become alive in your mind, you'll know how to draw them.
Good luck and have fun!
John is the author of four books for children: A Froggy Fable, Sticky Burr: Adventures in Burrwood Forest, The Clever Stick, and Sticky Burr: The Prickly Peril. By day, he designs games, websites, software and animated films for children's media company FableVision. Check out his blog for updates on John's online comic strip, films, puppet design and other projects.