To use a picture from your computer as your background, upload it to a free image hosting site. The site will give you the image's URL after uploading.

I am in a dreamweaver class in my college and I made a decent background image in CS2 for my HTML project for my web design class. Anyway, I had made a table at 1024x768 res., then put the ...

Repeat until you have a nice assortment of background colors saved to that folder. Switch to Terminal and repeat the steps to set an image as the window background.