Just go to the Menu and press "My Stuff." From there, go to "Picture" which will take you to the pictures menu. Select the Picture that you want as your background. Select "Set as" on the bottom of the screen, and then select "Wallpaper." That's all there is to it! You will have to use Bluetooth to get the picture file onto your phone, unless you have it saved on your SD card or received it in a message.