1. Get/Choose a photo editing program that can handle VTF (Valve Texture Format)
-For Photoshop CS2/CS3 you can use the plugin
here
2. Find an image you would like to use
-Here are some good ones
3. Open the new file in your photo editing program and resize the image to 256x256
4. Edit as you wish
5. Save as VTF
6. <More to be added in a sec>
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