Part of the Khao Laem Ya–Mu Koh Samet National Park, all visitors will be charged an entry fee once on the island (the main pier is Na Dan). Ferries depart from Ban Phe Pier on an hourly basis and drop tourists off at major beaches. Most high-end resorts offer boat transfer services, which leave from a private pier. It’s wise to inquire beforehand.
Once on the island, your transport options are limited to either songtaews (passenger-carrying diesel pick-up trucks) or speedboat rides between major beaches. Renting a motorbike is possible but not recommended as more than half of the roads are unpaved and are extremely narrow and hilly.