Vietnam is a culturally diverse and fascinating country, and is often a big step away from familiar cultures for visitors to the area. It has a variety of different climates, ranging from tropical to temperate mountainous zones, and the country experiences a high amount of rainfall and also some very strong sun, making it also very humid. For those flying in from Europe or the USA, it can be very difficult to know what to expect upon arrival.
The first thing to consider after booking your flights is to create a rough itinerary. This way, you can start to predict which areas you are going to be in and which vaccinations you may or may not require to protect yourself against infection. The zika virus is a risk in Vietnam, and travellers should take steps to prevent mosquito bites and sexual exposure to this during and after the trip. This is particularly dangerous for pregnant women as it causes serious birth defects, and so it is worth considering postponing your trip if you are expecting. Hepatitis A and typhoid are also possibilities, and it is worth checking with your doctor that you are protected against these before travelling.
Depending on what regions you are visiting, malaria can be a problem, but do be aware that preventative medication against this is very strong and can cause sickness in itself, so it should only be used if necessary. Rabies can also be found in some of the animals, so for travellers involved in outdoor activities, particularly in rural areas, and for people working with animals it is worth protecting yourself against this also. Yellow fever is not a problem in Vietnam, however if you are travelling from a country with a risk of the virus, you will require proof that you are vaccinated against it. It is usually considerably safer to get vaccinated from your home country before travelling than to get vaccinated upon arrival, and sometimes the vaccinations take a few days to become effective, so do ensure this is done before the start of your trip. It's also worth taking a small first aid kit with you, just in case, and it is also worth checking that your travel insurance covers everything you intend to do.
While it is very important to try the food of the culture on your trip, also be aware that unsanitary kitchens and a drastic change of diet can have very unfavourable effects on your body and potentially ruin your whole vacation. Immerse yourself into the new cuisine slowly, and don't eat from anywhere that looks too unclean.
After you have your itinerary, you can start to book accommodation, transfers, and to plan out all of your activities, from which you can start to pack your luggage accordingly. Everybody hates travelling with too much stuff, and there is a real art to packing light which will make all your transfers considerably easier. Vietnam experiences a whole plethora of different weather conditions, often all in the same day, so lightweight and multipurpose outdoor clothing is the most effective solution to ensuring you have the lightest baggage possible. A completely waterproof rain jacket is absolutely essential, but do be aware that the country is quite warm and so pack a small and light one. Strong sunscreen and polarised sunglasses are also very important, and due to the tropical conditions in parts of the country, it also pays to have some tropical grade insect repellent. The mountainous areas are a little cooler, and the temperature drops off a little at night, so make sure you also have some lightweight warm clothing with you as well as plenty of light clothing for the warmer weather. Aim for layering as this minimises packing and maximises the effect. Take some sturdy walking boots for hiking and some flip-flops for the beach. At least one swimming costume is a good idea, as you will likely spend a lot of time in the water.
The best way to obtain a visa for Vietnam is through the official government website, and all of the information can be found at https://vietnamvisa.govt.vn. Some nationalities can bypass this if they are staying for a short time, however you should absolutely ensure that you follow the correct procedure for your country and not make assumptions.