Need help using wallpapers? That is no problem! I'm here to help you! This is very simple. (wallpapers are the same thing as desktop backgrounds)
First, open up the image you would like to use for your wallpaper. For instance, this one.
All you need to do is right click, and on the drop down menu that comes down, choose 'Set As Background'
Minimize everything you have open, then whalah! Your desktop now changed!
All done!
By: Sugar