Make your own way to the Visitor Center at Joshua Tree National Park to meet your instructor.
Begin with a review of basic safety guidelines, then go over the function of each piece of the provided equipment. When ready, set off on an easy to moderate level hike to reach the first spot for your rappelling lesson.
Expect to learn to rappel on your own, and have a back-up line provided by your instructor. No previous experience is needed for this beginner lesson that is suitable for most people with a moderate level of fitness.
Bring comfortable clothing, sturdy walking shoes, enough water for several hours, and a snack or lunch. If you like to take photos, be sure to take your camera as there are great photo ops in Joshua Tree National Park.