My process for an illustration starts with a sketch for planning. I was asked by a local comic book artist to do a piece for his next issue of Meteors and Milk. I began with a sketch of his 2 main characters and my main character Jack.
I usually put each character on ther own layer and go through from the very front character all the way to the background, organizing my layers to make the process easier. Then I do all the line work with the pen tool and play with fill colors until I get something I like.