Here's my process of creating my illustration "momentum:"

I started with a very rough thumbnail sketch.

I scanned in the thumbnail and printed it out larger. Then I worked roughly over that in pencil, refining and moving things. On top of that pencil work, I refined more with pen and made some more decisions. If you notice the boy's legs in the foreground I decided his position was too placid and my little pushing gesture is at the bottom.

I then worked on top of that with tracing paper to move things around and draw even more refined again.

After I scanned that in, I could move or shrink things with Photoshop instead of redrawing the entire boy smaller, for example. The changes here from the previous one are that I shrunk and moved the boy, and I tipped the swing and shortened the ropes.

And finally when I print that out, I can carefully draw the final line drawing exactly how I want it on another piece of tracing paper on top.

I scan the final line drawing and first do color testing with Photoshop--quick coloring in of areas with flat color and making color adjustments. Finally I make swatches of all colors to sample from for the final, then erase this temporary sloppy color.

I fill in each element by selecting an area one by one and "cutting" and "pasting in" different scanned fabrics.

Finally I add a lot of white to the edges of things, and my finishing touches for this one are little shines on some things.