Normally for morning flights , i try not to sleep the nite before ; even if its a short 2hrs flight. This way , I sleep thru the flight and bus journey and it'll feel like only 10mins from my house (west Sg) to Pattaya! If reach Subv. Airport tired , look for the Bell girls early and sleep at a bench. They will wake you when its time to leave.
Other things to kill time are to hit the basement local thai hawker for cheap but good makan or the foot massage at the corner of the 2nd floor (i think!). Not very expensive but not worth if on the way to pattaya. Can also go to the floor where the bus comes or the floor with all the fast food resturants and bio the chabos! Last time I went , there was an angmo incentive group and they had girls in traditional custome to welcome them. Showed a lot of shoulders and a little bit chowkeng!
