Admission to Wadi Rum Protected Area is controlled and all vehicles, camels and guides must be arranged either through or with the approval of the visitor centre. Essential items to bring include a hat, preferably with a brim to keep the sun off your neck and face, sunscreen, sturdy footwear and water. Warm clothing, including gloves, is essential in winter.
If you are camping (including at the Rest House), bring along a torch (flashlight), a book to read and a padlock (many tents are lockable).
The Bedouin are a conservative people, so dress appropriately. Long shorts and sleeveless T-shirts for men and women are just about acceptable around the Rest House, but baggy trousers/skirts and modest shirts/blouses will save you sunburn and earn you respect from the Bedouin, especially out in the desert.