Swank up your next Caribbean stay at Mustique Island & Villas. Aside from total relaxation, there are few rules at this boho-chic, celebrity-favored hideaway in the Grenadines. The island, once home to Princess Margaret, holds over 100 unique, fully staffed villas — some on secluded beaches, others hidden atop lush hills. Play tennis, ride horses, enjoy a beach picnic, hike, swim with sea turtles or go diving and deep-sea fishing. Mingle at one of four restaurants or dance the night away at Basil’s Bar. Attend the island-wide cocktail party hosted at the 15-room boutique hotel, The Cotton House, every Tuesday night — shoes optional.