I'm going to be starting a series of tutorials to help other people learn to make sigs and avatars. This one will be for Photoshop(I have Photoshop CS) but I can do ones for Paint Shop Pro or another program if someone requests it. I've learned to use a good bit of the image programs.
Pt. 1-Just a basic icon.
To start you'll need to be familiar with Layers tool panel.

To see if its activated, at the top click on Window->Layers or press F7. It should be in the right hand corner of your screen.
Now open the base you want to work with(
Using Ctrl-O for an already saved picture or Ctrl-N for a new image and then paste in whatever picture your going to use). I'll be using one I pasted in.
The starter image:
Your first step will be to adjuct the Brightness/Contrast. Use the sliders to adjust till your happy with the color.
Where to find the brightness contrast tool!
My result:
