Charlie Layton had just been laid off from his full-time graphic design job when he got a call from Velo Press, a publisher of books all things athletic. "Before I could finish my first beer, they asked for 60 illustrations," he said.

Layton, who lives in Philadelphia, had been doing small illustration jobs on the side, but this was his first step into becoming a self-employed illustrator whose work has appeared in books, advertisements, posters and magazines. He's lost count of how many books he's done for Velo Press, both inside illustrations and covers.

His latest project is the illustrations for Trailhead: The Dirt on All Things Running, written by Lisa Jhung. The book is a guide not just on how to become a trail runner, but how to do it right, including injury prevention and rules on running the trail.

"I do a lot of work for them, but this was definitely the most fun," said Layton. "They said the drawings could be more humorous, and I could put a bit of personality into them."

And he does. An illustration about trail etiquette is drawn in the fashion of Chutes and Ladders. An illustration of how to do strength training exercises features a cat crawling over the guy doing the moves. And in a section about going to the bathroom on the trail, he drew a poop fairy. Yes, an actual fairy.

"Every illustration description was 'add humor if you see possible,'" he said.

When Layton's on the trail, he's more like to be on a mountain bike than on foot, but he drew a lot of inspiration from the Fairmount Running Club, a group he runs with regularly.

If you'd like to know more about trail running, Trailhead is now out in stores. I'll be interviewing author Lisa Jhung later this spring about the sport, too.

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