Click a link below for the appropriate size of your desktop.
When the image opens in a new browser window, right click
on it and choose "set as background", or "set
as wallpaper"
For Mac users. Click on selected image and drag onto your
desktop (or hold down mouse button over image link and save
file to desktop). Hold down the Control button on the keyboard
while clicking on an empty area on your desktop. Select "Change
Desktop background." Navigate to the photo that you have
chosen and click on it.