In terms of clothes items like bathing suits will of course be standard. However, don't forget to pack a few extras as well as a nice cover-up, like a beach sarong. An extra suit will come in handy while the other one is drying. Pack two or three pairs of comfortable shorts, in light material such as cotton or soft denim. These will be nice for a quick stroll or jog on the beach or for wading. Bring along two or three cotton t-shirts, shirts or tank tops. These should nicely match with the shorts. A few flowery or cotton dresses will also be nice for the evenings. Especially if you want to visit a beachside restaurant or club. If the travel is not to a tropical destination, then the nights could get cold. A light jacket and a pair of trousers will be useful when stepping out in the evening.