To add an animated background to your signs, you can open the MangoSigns slide editor and find the Animated Background app on the left hand slide of the editor. When you click the Animated Background icon, you will see a list of all of the Animated Backgrounds currently available.

Once you click on the animated background and click the Plus button, the animated background will be inserted into your slides. You can adjust the colors within the animated background through the Settings panel in the MangoSigns slide editor.