The texture and colors of these sunsets were always impressive and astounding, it had you glued to the sky like when your watching your favorite show on TV and the next episode was always better then the previous episode never disappointing.
Koh Samui can be found on the Gulf of Thailand in the south of Thailand, there are numerous direct domestic flights from Bangkok airport to the island and there are also some international flights that fly into Koh Samui airport. If your wanting to do it the cheaper way as for backpackers you can fly from Don Muang airport in Bangkok, to Surat Thani Province, then be transported by bus from the airport to the Donsak Pier and take the ferry across the Gulf of Thailand to Koh Samui island, it really works out a third of the cost compared to flying direct to Koh Samui island, it might take longer but you really get to see more of the country side and probably catch the best sunset while crossing over by ferry over the Gulf of Thailand, that's if your on the last evening ferry.
@uwelang