1. Go to My account.
2. Upload your own background image by clicking "Choose File" in the "Background Image" section.
It is recommended to Keep the important information close to the left of the image. If you want your image to tile, check the 'Tile Background' option. If you want to customize the background color, click the color picker at the "Background color" section. If you add a background image too, make sure that it nicely blends into your background color.