As you'll likely be spending much of your time at the hotel dressed in just a robe and slippers, you won't need to take too many belongings. Besides comfy clothes to slip into after your treatments, essential items like toiletries and underwear should be right at the top of your packing list. Of course, if you intend to use the swimming pool or participate in exercise sessions, toss a swimsuit and some gym clothes into your bag too. Finally, leave the electronic devices in your office and take a magazine instead. It is, after all, meant to be an escape from the real world.