You can find your unique referral ID URL on the "Billing" tab of your account. Once a month we'll count up the accounts that signed up using your referral ID and that have paid for their first month of service, and we'll send you a payment on PayPal. Obviously, you'll need to tell us your PayPal account so we can send you the money. Participation is subject to our Terms of Service. The referral money can be claimed only once per account that signs up.