Quickrunner

I like how this turned out. Last night I finally got around to pulling out my old colored pencils, and drew a picture with them. I noticed one major anatomical problem, with one leg wider than the other when the other leg should have been wider than the one. There's probably more errors, so feel free to point them out. That's what happens when I don't use my ruler. Plus my coloring was a bit on the sketchy side and had virtually no shading, advice on making it look more professional would be appreciated.
Now, it is very important for me to say that I copied this pose and most of the clothing style out of the book "Action Cartooning" by Ben Caldwell, which is the most amazing drawing book ever! Before buying this book, I didn't know the first thing about drawing characters who aren't standing around doing nothing. But now I'm learning a lot.