Thai culture, explained

Start with the wai and the head. Return a wai from an adult with one of your own; you don't need to start one with a shop assistant or a child. Never touch anyone's head, and don't point your feet at people or at a Buddha image.

Keep your voice down on public transport and your temper anywhere. Raising your voice in a dispute loses you the argument, whatever the facts, because Thais read it as a loss of self-control. The idea behind much of this is kala-thesa, time and place: what's fine at a Songkran water fight is wrong on the BTS.

Dress for temples. Shoulders and knees covered, shoes off where others take theirs off. Many big temples turn away shorts and vests at the gate.

The catch with all of this is that nobody will tell you when you get it wrong. Thais are polite to visitors and rarely correct them, so a smile is not proof you've got it right. Watch what the people around you do, and copy them.