1) Right-click on the full-size image and select "Set As Wallpaper" from the pop-up menu to make the image directly into wallpaper.
or 2) Select "Save Image As..." and save it to the "Windows" directory; then in the "Display" Control Panel, choose "Background," and in the "Wallpaper" window, choose the new picture and click "OK."
MAC OS 8x:
1) Click and hold on the image, then save it to your hard drive.
2) In your Desktop Pictures control panel, click "Select Picture" (if you already have a picture, click "Remove Picture" first, then "Select Picture") and choose the image.
3) Click "Set Desktop" and close the control panel.
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