As you're likely to be spending a good deal of your time dressed in just a robe and slippers, you won't need to take too many belongings. Besides comfortable clothes to slip into after your massage and spa treatments, essentials like underwear and a toothbrush should be at the very top of your packing list. Of course, if you plan to make use of the resort's swimming pool or join a couple of exercise sessions, squeeze a bathing suit and some workout clothes into your bag too. Finally, leave your electronics at home and bring a good book instead. It is, after all, meant to be an escape from the real world.