ALWAYS drink plenty of bottled water. During the summer months you should be drinking a minimum of 2 liters per day. If you drink tea, coffee & alcohol you should increase you water intake accordingly as these will dehydrate you.
Before venturing out from your hotel, ensure you have a hotel business card from the reception desk. This will make your return to the hotel in a taxi or cyclo much easier.
For longer excursions from your base hotel, it is always a good idea to carry a roll of toilet paper in your day pack. You never know when you will need it.
Always dress appropriately. Not only for the prevailing climatic conditions, but also not to cause offense to the local people. Vietnamese have conservative dress codes and it is only in larger cities that these codes are relaxed a little.
Always leave your excess cash, airline tickets, passports and valuables with the hotels safety deposit facility.
Always be aware when entering someone’s home as at some homes it is a must to remove your shoes at the front door.
Always ask his or her permission first when taking a photograph of someone. If they indicate that they do not want you to, then abide by their wishes. DO NOT push the issue or offer money.
Never wear shorts, dresses or skirts, or tops with low-neck lines and bare shoulders to Temples and Pagodas. To do this is considered extremely rude and offensive.
Never give your empty water bottles, sweets and candies to the local people when trekking through ethnic minority villages. You cannot guarantee that the empty bottles will be disposed of in a correct manner and most of these people do not have access to dental health. If you would like to give pens/paper, ask your guide to introduce you to the local teacher and give them to the teacher for distribution.
Never sleep or sit with the soles of your feet pointing towards the family altar in someone’s house.
Never venture out from your hotel with more cash than you really need for that day. It is NOT something to be paranoid about, simply do not make yourself a target for pickpockets or drive-by bag snatchers in the big cities. Ho Chi Minh City seems to be a little worse than anywhere else in Vietnam is. On the whole it is one of the safest countries you could wish to travel in.
Never lose your temper in public or when bargaining for a purchase. This is considered a serious loss of face for both parties. Always maintain a cool and happy demeanor and you will be reciprocated with the same.
Never try and take photographs of military installations or anything to do with the military. This can be seen as a breach of national security.
Never take video cameras into the ethnic minority villages. They are considered to be too intrusive by many local people.