You can get to Koh Tao a number of ways...

Most popular are the speed ferry routes from Chumphon or Surat Thani on the mainland.

Both Chumphon and Surat Thani can easily be reached from Bangkok via rail, road and air.

Frequent day-time boats also arrive on Koh Tao from Koh Phangan and Koh Samui.

Large car/bus ferries serve Koh Samui from Surat Thani (Donsak Pier) allowing vehicles to be easily and cheaply brought to the island.