1. Log in to the site by entering your email address and password as you normally would. 

2. Once you're logged in to your personal account dashboard, you'll select "Payment Methods" from the menu on the left-hand side of your screen. 

3. This page will have all of the cards you have currently on file for your account by the card type, the last 4 digits, and the expiration date. (You also have the option to select which card you'd like to save as your "default" card)

4. To update card information (ie. expiration date), simply select the card you'd like to update and fill in the information. You'll also see the option to add a new card, or to delete cards that have been previously saved to your account. 

5. Remember to hit "Save"!