How to swap iPads with my wife

I have an iPad WiFi 64g and my wife has an iPad 3g 64g. Now I want to swap them over as I need the 3g capabilities. How can I do that? And we need to make sure that we each retain our own files, settings, apps etc.The switch is not a problem.1. First backing up your each iPad. 2. Then what you need to do is to restore each iPad with backup of the other iPad via iTunes. There is a unique serial