I've been to Koh Tao on two occasions now, first as part of our worldwide trip in 2013, we needed to wait for our visas to come through from India to the embassy in Bangkok so we split our time in Bangkok city and down on Koh Tao island doing a PADI open water scuba diving course while staying at the Sairee beach front Coral Grand Resort.
Koh Tao is world renowned for PADI courses as you pay a bargain compared to doing the same course in other parts of the world such as Cairns in Australia. The course is five days long and starts with two back to back days in the resorts swimming pool getting to know the scuba gear and learning your technique. This equaled to nearly ten hours per day in the pool and was quite frankly exhausting, our dinners were spent on site as a group and then hitting the sack to preserve our energy for the next day of lessons. Days 3 to 5 were out on the sea, doing the dives and the underwater skills required to pass.
Sadly I didn't make it to the last day as I struggled with some of the maneuvers (such as taking your air plug out, blowing bubbles and then putting it back in) or removing your goggles and putting them back on while clearing the water out from them and your eyes - at 18 feet below water. Cue small panic attack. My other half on the other half passed with flying colours and the rest of the team even made an underwater music video on the last day to the harlem shake which we all sat around and watched with some beers on our last night on the island. Pure magic.