You may view or change your subscription type and basic credit card information by going to Account Name > My Account and viewing the Plan & Billing
When choosing or changing your subscription, you have the choice of either a monthly subscription at $49/month, or a yearly subscription for $480/year.
Click on the arrows to the right of the plan, and select either monthly or yearly in the menu:
Once selected, you can add a credit card, or change your current credit card by clicking in the Card Number Field:
Input the card number, then add/modify the Name and Expiration Date. Add in the CVV number from the back of the card (For AMEX it is the 4 digits on the front of the card) and click Save Plan & Billing Info: