Go to your home screen and long-press any blank space. A small window will appear. Tap "Set Wallpaper & Style."

Tap the ">" icon next to "Wallpaper" to go to the wallpaper settings.

Choose from a variety of beautiful images already provided, or tap "My Images" to select your own picture.

If you want to use your own pictures, click the first folder "My Images". And select your favorite picture. You need to put your pictures into the "My files - Downloads" folder in the file system. Then they will show up in "My Images" for wallpaper setting.

After all these steps, you will see your new wallpaper!