As you leave one of the many Disney theme parks, be sure to have your hand stamped as you exit in order to be granted readmission into the park later that day or evening. In addition to the hand stamp, be sure to retain your ticket stub. The hand stamps are designed to be water-resistant, so don't worry if your hand gets wet if you choose to return to your hotel in the middle of the day to go swimming, and then want to return to the parks later that evening. Try to refrain, however, from scrubbing your hands clean with soap until your day's visit to the park is complete.