Joining Vuse Rewards is easy (and free).
Start by creating an account on vuse.com. As you complete the sign-up process, you'll be prompted to participate in Vuse Rewards. Keep the checkbox checked and you'll automatically join.
If you already have an account on vuse.com, you can opt-in to Vuse Rewards in your account profile. Just visit the Vuse Rewards section in your account and toggle on the Vuse Rewards to join.