1. First, I doodle on my Wacom in Illustrator. I used to sketch in pencil, then scan, then ink, but lately I've just been drawing straight in Illustrator. I like the control it gives me. Here I've drawn a lovely young lady in a loose-flowing top.
2. Once I like the inks, I export to bitmap and open it in Photoshop. I'll usually do a little clean-up on the lines. The important thing before coloring is "flatting." I select each part and assign it a shade of gray. This lets me select only those areas when I'm coloring later.
3. Spend some time coloring in Photoshop. And, she's done. I'll probably go back and give color to all the lines, instead of leaving them black.