1.) Once logged in, select the drop-down menu from the upper-right-hand corner of the landing page. 

Select “My Account” from the drop-down menu. This will take you to your account dashboard.

2.) Click on the "Payment Methods" tab.

If you wish to edit an existing payment method that you've previously saved, it will populate here. Otherwise, click on the "Add payment method" button.

3.) Input your card number, expiration date, and CVC.

Click on the "Add payment method" button to save the details to your account.