Help with buying AP before trip

Planning on buying an Annual Pass for our upcoming trip. I know that you have to visit the parks and activate your pass before they will mail your magicband and offical AP card, so I plan on linking my AP voucher to the magicband I will get with our on-site hotel reservation.

What do I do about using my AP discounts at the parks since I won’t have the official card that they seem to mail out? Will I get a temporary card to use for discounts while on our first trip of the year?

When you take your voucher to guest services they will give you your AP card to show for discounts. Almost every place asked me for my picture ID too.