The Maldives is hot throughout the year. Light, summer cotton and linen wear is ideal. Pack lots of tee shirts, beachwear, light skirts, cotton shirts, slacks and shorts. At the resorts where you will have to walk on soft sand most of the time, going barefoot may be ideal for some.
However on visits to inhabited islands, where most of the streets are of compact sand, or Male where most of the streets are paved, casual shoes or sandals are easy to walk on.