Wrote this a while back and didn't have time to finish it then before getting busy again:
Upon return from Korat, I took a day in Bangkok with my sister, then during her work week I went to
Ko Samed (aka Koh Samet). The idea was I'd spend two days there and head back for touristing on the weekend; then my sister decided maybe she wanted to lounge on the beach, and I decided maybe I was tired, and so plans morphed to the lazy end of the spectrum.
I went to Mochit terminal, where all the intercity buses go, and tried to hire a bus. Accidentally, I hired a minibus instead. With my usual minibus luck, it took 4h rather than 2.5h (my sister also hired a minibus, but she made it in the normal time, and that's how long it took to get home later). No worries, I got there in plenty of time for the ferry and wandered down to a "cheap" place on Ao Nuan that the Lonely Planet recommended. Fuck that shit: dogs barking, bugs in the bed, disgusting shower, nasty iced coffee, 800 baht for a queen bed. Granted, this was the first place that was vaguely liveable -- the North of the island, where the main pier is, is completely overrun by crowds at the plethora of noisy beaches. The further South you go, the better. I must admit the beach at Ao Nuan was nice; I leapt into the sea. Normally I only last a few minutes in sea water, maybe 20 minutes in the Florida Keys, before getting a chill. Here I lasted more than an hour, until I got bored. Unfortunately, I had forgotten to slather sunscreen on my shoulders at all, since I was wearing a tshirt, and I hadn't put much on my forehead nor any on my part given I was wearing a hat -- an hour in the sea without those clothes earned me a good lobstering.
The second day, a Friday, I put on lots of sunscreen and headed South. The beaches really do just keep getting more pleasant. I checked into Samet Ville Resort, the only place on Ao Wai and the furthest south you can go before a really high-end resort that has guards to make sure the hoi polloi don't get too close to their beach. The LP description is entirely accurate: shabby if you think of it as a resort, but very nice if you expect a 2-star hotel on the beach. 2000 baht a night -- $60 for two beds you can sleep on (remember: I was there with my sister), A/C, a shower that is not wonderful but not repulsive, and, almost worth the price on its own, an absolutely gorgeous largely secluded beach.
Saturday, my sister showed up with a friend of hers who was working through something tough (what, I don't know) and needed to get out of town. She was extremely thankful that my sister and I would let her in to our trip and include her in anything. I can't exactly read my sister's mind, but personally it seemed totally natural -- why wouldn't we want to hang out with a cool person, particularly if she needed it?
Sunday was much like Saturday, except that we took the second-to-last ferry back to the mainland, and got a minibus back to Bangkok. The process was comfortably befuddling: we ask around for a ferry, eventually realize that all the companies that are competing are charging the same price, leave at the same time, and take the same amount of time, so we go with the return ticket I already have (saving 50 baht -- not quite $2). Then we get to the mainland, wander down the street on a vague hunch there might be a bus station that way, inquire somewhere, they respond "17:10" which is 20 minutes thence. We take that as probably meaning that there is a minibus at that time going to Bangkok, money changes hands, pieces of paper are scribbled on, and we are invited to wait. Then a minibus shows up, we get on, it drives down the street, then drives back, then down the street again, and eventually we are on a highway. By this point, I had gotten mostly comfortable being clueless, but given I had my sister to chat with, I noted some strangeness. She had never minibused before, so when we stopped for gas, I had to tell her how to react (you get off, you shop for ten minutes while they gas up, then you wait a minute or two until they come to pick you up).
Monday was home: up at a ridiculous hour, walk out to the lobby to see a downpour (one of the first of the rainy season), wonder how to hail a cab, then a cab shows up and disgorges a couple who bum 100 baht off the security guard to pay the fare (?!?), so as soon as they pay, I get in and off to the airport. No real drama from then on; my trip was over!
Tl;DR Thailand is fucking awesome, you should go!