1. Click on the Settings Icon. It is in the upper right corner of the page.
2. Login to your account using your username and password.
3. Click on the "Turn On Auto Renewal" button.
Turning off the auto-renewal feature will keep your account active until it reaches the Expiration date, which is either 30 days or 1 year from your Activation date. If the account is canceled, upon expiration date the account will revert back to a free account.
When you re-activate your account (turn on auto renewal), if the expiration date has not passed your account will simply restart the prior billing cycle. 
If the expiration date has passed a new activation date will be set and your card on file will be charged. Click on the Active button to start a new account. 