I found the trick to driving in Thailand was to drive aggressively rather than defensively. ie racing up to stop signs and jumping in front of the then harsh braking victim on the main road.I love the way the Thais behind then all follow closely like train carriages once that right of way has been broken

Even though I believe the majority of Thai drivers had a gun under their seat I found them a lot more courteous than these road raged horn bibbing wankers in most other countries.
The main secret to staying safe on Thai roads imho though is to stay off the fuckers after dark.