You can leave that huge, expandable suitcase for another time because you won't need to bring much with you at all. You'll probably spend a lot of time lounging around in a bathrobe and slippers, but usually these are supplied to guests by the resort. If you're planning to go for a dip in the pool or enjoy some water-based activities, pack your bathing suit and extra clothes. Casual, non-restrictive garments are perfect. Considering taking an exercise class? Bring sportswear and a pair of comfy trainers. Oh, and remember to bring your toiletries and other personal effects!