Windows
Left-click your mouse on the appropriate resolution image 640x480, 800x600 or 1024x768. Right-click your mouse on the photo and select "Set as Wallpaper" from the menu.

Macintosh
Drag the appropriate resolution image 640x480, 800x600 or 1024x768 to your computer desktop. Next, open the "Appearance" control panel, click the "Desktop" tab, then click the "Place Picture" button. Locate the image in your file directory and click "Choose." Click "Set Desktop" to apply the wallpaper.