Kohtao Daimon Tour

If you're coming to Koh Tao for the water and don't want to spend your first morning wandering the pier comparing hand-painted signboards, booking a local operator ahead of time saves you a lot of faff. This one runs island-based excursions and trips out to the snorkeling spots, and it's the sort of thing that suits people at either end of the confidence scale, from first-timers who want someone watching them in the water, and people who just want a boat that goes where the coral actually is.

The hours are listed as round the clock, which in practice means inquiries rather than departures. Nobody is taking you out at three in the morning. Use it as a sign you can message at odd hours from another time zone and expect an answer at some point. There's no phone number in the listing, so the website is your route in.

Sort your booking before December if you're traveling in the December to April stretch, because that's when the island fills and boats go out full. Bring reef-safe sunscreen and a rash guard. The Thai sun on open water is punishing and a t-shirt in the sea is not a good look on anyone.