I'll tell you how I do it through some simple steps.
1. First get the picture you want to edit. Save it to your computer. You can find these at the Charart Talk Page. (I suggest you start out with a kit, they're the easiest to work with when editing.)
2. (There are several programs you can use, but I use pixlr.) Go to www.pixlr.com
3. Open the image, pick a base color, and click on the paint bucket. Then click on the cat.
4. Make the ears pink, and then use the blur tool (Shaped like a raindrop) to make it blend in.
5. Go back to what your base color was, and find a color a little darker. Surround the cat with it, then use the burn tool to officially do the shading. (Burn tool looks like a fist)
6. Color in the eyes, and then make a white and black dot in the eye to make it's pupils.
7. Color in the nose and add finishing touches.