1. The Lao word for 'hello' is 'sabai dee', usually said with a smile. Touching or showing affection in public will embarass your host.
2. In Laos your head is 'high', your feet 'low', using your feet for anything other than walking or playing sports is generally considered rude. Do not point with your feet/toes and do not have your feet raised/or propped up on tables.