PC Instructions: Choose your image and click on your resolution. Position your mouse over the image. Once the full image has downloaded, right click your mouse. Choose “Set as Background” or “Set as Wallpaper” from the popup menu. Mac Instructions: Choose your image and click on your resolution. Control-click on the image and select “Save Image As” or “Download Image to Disk” (depending on your browsers options). Choose a location and click “Save”. Open System Preferences and click “Desktop & Screen Saver”. On the Desktop page, click “Choose Folder” and navigate to the saved image file. Select it and click “Choose”.