Do's and Don'ts

The Monarchy
Thai people have a deep, traditional reverence for the Royal Family, and a visitor should be careful to show respect for the King, the Queen and the Royal Children.

Religion
Visitors should dress neatly in all religious shrines. They should never go topless, or in shorts, hot pants or other unsuitable attire.It is acceptable to wear shoes when walking around the compound of a Buddhist temple, but not inside the chapel where the principal Buddha image is kept. Each Buddha image, large or small, ruined or not, is regarded as a sacred object. Never climb onto one to take a photograph or do anything which might indicate a lack of respect. Buddhist monks are forbidden to touch or be touched by a woman, or to accept anything from the hand of one. If a woman has to give anything to a monk, she first hands it to a man, who then presents it.

Social Norms
Thais don't normally shake hands when they greet one another, but instead press the palms together in a prayer-like gesture called a wai. Generally a younger person wais an elder, who returns it. Thais regard the head as the highest part of the body, literally and figuratively. Therefore, avoid touching people on the head and try not to point your feet at people or an object. It is considered very rude. Shoes should be removed when entering a private Thai home. Public displays of affection between men and women are frowned upon.

Information from Tourism Authority of Thailand (TAT)