The journey is in two parts:

First you travel from Bangkok, Singapore or Surat Thani by plane, train or coach

Then you travel to Koh Toa by boat.

By plane from Bangkok or Singapore to Koh Samui

Bangkok Airways provides over 10 flights a day from Bangkok and a daily flight from Singapore to Koh Samui. Thai Air also offers daily flights to

Koh Samui and Air Andaman flies four times a week to Chumphon. From Koh Samui or Chumphon you need to take a ferry to Koh Tao.

By plane to Surat Thani transfer to Koh Samui

Check out flights to Surat Thani

Lomprayah and Seatran will take you directly from Surat Thani Airport to Koh Samui where you need to catch a ferry to Koh Tao. Your alternatives

are to take a taxi to Donask, or go to Surat Thani and take a bus to the ferry terminal and from there catch the ferry from Surat Thani to Koh Tao. 

By train from Bangkok to Chumphon or Surat Thani

A delightful train journey from Bangkok to Chumphon or Surat Thani for those travellers not in a hurry. You experience a real taste of Thailand.

1st and 2nd class air conditioned and fan-cooled sleeping carriages and air-conditioned and fan-cooled ordinary carriages are available. Thai Train Ticket. 

On arrival at your destination you need to take a ferry to Koh Tao.

By bus from Bangkok to Chumphon, Surat Thani or Koh Samui

Coaches leave the Main Bus Terminal for Chumphon or Surat Thani or Koh Samui. Air-conditioned coaches are much more comfortable. The journey

takes several hours. From Kaosarn Road - daily bus & mini bus depart at 20:00-21.00 and arrives in Chumphon at approximately 04:00.  On arrival

at your destination you need to take a ferry to Koh Tao.