Step 1: Take pictures of yourself with Photobooth. Pose until you naturally distorted look like a caricature of yourself.
Step 2: Trace those pictures quickly in different layers in Photoshop Elements using a drawing tablet.
Step 3: Turn off the photo layers and adjust, change slightly, etc.
Next steps, color these and do some more. Work up some crazy simplified versions of them. I think this may be a good way to develop characters. The above is roughly 2 hours of work. More to come…