The greatest seasons to visit Vietnam are from October to April although there is no one ideal period due to the vast variances in latitude and altitude. It's a great place to go any time of year.
Summer from May to September is also the ideal time to travel in terms of best price.

Dress modestly, covering your shoulders and knees, when visiting religious places, the countryside, and the Ho Chi Minh Mausoleum. Before visiting a temple or pagoda, don't forget to take off your hat and shoes.

To contact the police, an ambulance, or general phone number inquiries in an emergency, dial 113, 115, or 116, respectively.
Sometimes the switchboard operators may not always be competent in other languages, it may be beneficial to seek assistance from the locals.

For foreigners, Vietnam is regarded as a safe place to travel. Sadly, there is a chance of pickpocketing in popular tourist destinations like Hanoi and Ho Chi Minh City. It is advisable to adopt sensible safety measures when visiting crowded areas. High-end gadgets and other valuables should generally be locked in your luggage or kept in the hotel safe. Additionally, a waist belt or bag that hangs around the neck might be used to store money, a passport, or other such items.

- Drink plenty of fluids during the day (2 liters).
- Do not drink tap water in Vietnam. Only bottled water is drinkable.
- Wash your hands frequently
- Avoid eating unpeeled fruit or raw vegetables and ice.
- Most important: trust your gut feeling. If you don’t like your food, stop eating and do a double check when eating from street vendors.

Do
- On a trip to Vietnam, everyone should keep the word "respect" in mind. It is reciprocal, and the Vietnamese are by nature kind and welcoming. Visitors are expected to treat them and their beautiful land with respect.
- Respecting their faith and its structures, such as taking off your shoes before entering a temple, is one of the absolute must-dos. If visitors plan to visit temples, they should dress modestly. It is nice to ask people's permission before taking their photo, right?
Don’t
- You should always use both hands while giving or receiving something. Even if you are on a tour, you will have plenty of free time.
- If you are traveling alone, you should have a map and the contact information for your lodging with you and should put any valuables you do not need with you in a safety deposit box at your hotel.
- You should always behave appropriately in public and never use your finger or foot to point. Additionally, touching someone's head is considered disrespectful.