You can manage your payment method in the Account section of your profile:

You can add more than one credit card as a payment method, and you can remove any card by clicking Delete. 

You won’t be able to remove a card that’s being used on a pending or active booking.

Note: You can add credit cards from the Payment Methods section of your account and the booking page window.

All major credit cards are accepted.

How do I add a discount code?