It is a ticketed event, but you do not receive your tickets until you arrive at Walt Disney World. When you first make your priority seating, Disney will require a credit card to guarantee the booking. You must cancel at least 48 hour in advance or your card will be charged.
If you are staying on property, you can pick up (and pay for) your tickets up to 7 days in advance at guest services of your resort. If staying off property, you'll need to arrive at Fort Wilderness early that night and you can pick up your tickets at the box office.
Have fun, the Hoop Dee Doo Revue is a blast!