

Do not step over a Thai persons legs or any body part, for instance if they are seated
Do not step over any food or drink on the ground
Do not embarrass a Thai person, or cause them to loose face
Do not swear at a Thai person. Even though the language may be different, they will know you are swearing
Do not loose your temper or fight with a Thai person. As a foreigner you will always be out numbered and the Police will favour Thai nationals over you
Do not point your finger at someone
Remove your footwear before entering any home. Many shops and businesses also require you to remove your footwear before entering. Just look outside the door before entering, and if there are shoes outside, remove yours too. If there are no shoes, youre probably okay to keep them on.
Do not offend Buddhism or the Royal Family in any way
Always respect elders, no matter what the situation
Do not point with your foot
Do not shout or argue in public
Keep any public affection to a minimum
Thai's greet each other with the traditional 'wai' and not with a handshake or kiss on the cheek. If a Thai wishes to greet you in a western way, wait for them to initiate it, otherwise keep your greeting traditionally Thai.
Don't worry if you forget something, just apologise if it appears that you have upset or offended anyone, maybe even do the traditional Thai 'wai'