General Advice - show respect and use your head and eyes and common sense will guide you well in navigating Lao culture safely.
When in Laos, try and do as the as the Lao do and remember; don't touch heads, don't loose your cool with people and don't flash your flesh. The rest is about manners, shoes left outside, accepting hosts' greetings and not upsetting religious feelings.
The Lao are very friendly and hospitable and a minimum effort will make your trip smooth and memorable.
Respect the culture and you will earn its respect in turn.