Originally posted by kcashner
You can request the rewards card on line or by calling the number on your statement (where it says "to request reward card"). Then, you can "reload" additional points to the card using the online feature.
To use the card, you take it to guest services on the ship or at any of the WDW resorts. They "take off" whatever the amount of your bill, leaving any balance on the card. It's really easy.
The only negative at all is that you want to only pay off your account, not put any "extra" toward your account as you cannot get the "money" back at the end of the cruise if you haven't used it. Thus, you are best off taking the card to guest services a day or 2 before the end of the cruise and applying it.