Go to "Settings", "Personalization", "Start". There you can set your background, tile transparency, and tiled or full background options. There has been background settings issues with some phones, so not everything may work properly. Some issues reported have been mis-aligned backgrounds, "gutters" or black bars on one side of the image, and skewed or fuzzy images. Also the "tiled" and "full screen" options have had issues on some phones as not working correctly. Hope that helps!