We took a longtail boat from the beach - there are plenty of them down there and you can just walk down and find one, you do not have to join a tour or pre-arrange a boat.
The island is fairly small and there is a sandbar that connects the two bigger parts of the island together. There is a viewpoint on the smaller island that is a bit of a climb, but the view is spectacular and worth the climb up the stairs. The beach is mostly crushed up coral from the reef that is there so it is not silky-smooth sand, but it is ok if you put down a towel or you can rent beach chairs there as well.
There is a restaurant and a bar there so food is available. You are not allowed to bring plastic bottles or cans onto the island.
We went for the afternoon, and it was quite nice to relax a bit, and take the climb to the viewpoint. There is some snorkeling off the beach, and we were able to see quite a few fish without going very far out.
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