Here's the Google Wallet FAQ. From it: "You will need to have (or sign up for) Google Wallet to send or receive money. If you have ever purchased anything on Google Play, then you most likely already have a Google Wallet. If you do not yet have a Google Wallet, don’t worry, the process is simple: go to wallet.google.com and follow the steps." You probably already have a Google ID and password, which Google Wallet uses, so signing up Wallet is pretty painless.