1.Try to learn as much as you can about the country or place your going to.
2. Learn from the locals, there are many sites that offer information from the locals.
3. Know yourself, what you can or can not eat, your allergies, your health level and how locals live (like you're going to villages where transportation are limited but you are very bad at hiking or walking long distance), etc.
4. Learn a bit (a lot would be better) about their language.
5. Know the laws and the do's and don'ts. Always kind but alert at the same time.
6. Be happy and enjoy the ride.