It depends on which tan you choose. The Full Body Spray Tan you can shower in 8 hours or longer. With the Express Full Body you can shower in 3 hours or less, depending on your skin type. Express tans are very popular because you can shower them off sooner and resume normal activities quicker.
No matter which tan you choose, you will also want to avoid any activities that include water or excessive sweating before that first shower.
Note: With Express Tans you can not keep them on longer than 3 hours. Click here for more information on Express Tans and how they work.