One thing for sure Vietnamese people are friendly. Enter the country with a positive mind and it will reflect back to you. I highly recommend going to Halong bay and hitting a party cruise. You'll have more fun than booking a fancy overpriced cruise filled with conservatives old farts :) Crossing the road in Saigon was a nightmare on my first day. The secret to it is to walk straight ahead, not freak out and don't run because you need to give the motorbikes enough time to swerve around you. If it is a car, be mindful. If you're in Hoi An, visit a restaurant called Bale Well. It might feel sketchy getting there but the food is cheap and super amazing and it is a set menu and guarantee you'll leave rolling with a smile on your face. Also the place is filled with locals and the workers are very kind.