1. Visa Requirements: Check the visa requirements for your country. Many visitors can get a visa on arrival or an e-visa, but this should be arranged before your trip. Ensure your passport is valid for at least six months beyond your planned stay.

2. Currency and Cash: The Vietnamese Dong (VND) is the official currency. While credit cards are accepted in many hotels and restaurants, especially in larger cities, cash is king in smaller towns and local markets. It's advisable to carry some cash at all times.

3. Health Precautions: Consult with a travel clinic for vaccinations and health advice at least a few weeks before departure. Consider vaccines for hepatitis A and B, typhoid, and other region-specific diseases. Always drink bottled water and avoid ice in drinks to prevent stomach upsets.

4. Local SIM Card: Getting a local SIM card for your mobile device is cheap and convenient. It ensures you have access to the internet and can make local calls. You can usually purchase one at the airport upon arrival or at local shops.

5. Dress Respectfully: When visiting temples and religious sites, dress conservatively. This means covering your shoulders and knees as a sign of respect. It's also practical to dress for the weather – lightweight and breathable clothing works best in the humid climate.

6. Transportation: Motorbikes are the most popular mode of transport, and you can rent one if you're brave enough to tackle the traffic. For safer options, use Grab (the Southeast Asian equivalent of Uber), taxis, or trains. Always agree on a taxi fare before starting your journey or insist on using the meter.

7. Learn Basic Phrases: Knowing some basic Vietnamese phrases will go a long way in endearing you to locals. Even a simple “Xin chào” (hello) or “Cảm ơn” (thank you) can make a difference.

8. Street Food: Vietnamese cuisine is delicious and street food is an integral part of the culture. However, eat where the locals eat, as their patronage is often a sign of fresh and safe food. Keep an eye on food safety and go to busy stalls with high turnover.

9. Bargaining: Bargaining is common in markets and street stalls. It's expected that you will haggle on prices, but always do so respectfully and with a smile. Know when to walk away if you're not happy with the price – often, the vendor will call you back with a better offer.

10. Travel Insurance: Never travel without insurance. Make sure you have comprehensive travel insurance that covers medical expenses, theft, and trip cancellation. It's better to have it and not need it than to need it and not have it.

Finally, immerse yourself in the local culture, be open to new experiences, and enjoy the diverse landscapes, from the Mekong Delta to the terraced rice fields of Sapa and the bustling city life of Ho Chi Minh City and Hanoi. Vietnam is a country with a lot to offer, and with the right preparation, your trip can be unforgettable.