I flew into Ho Chi Minh from Kuala Lumpur and decided to spend the first two days getting to know the city. From the airport I hopped in a cab to a hotel I had pre-booked, a budget-midrange option called Elegent Inn Hotel. The place gets great Tripadvisor reviews and I wasn't disappointed. Location is ideal, breakfast is included, rooms are large, clean and serviced daily and the staff is very friendly. They can also book onward travel and many tours.
My first taste of HCMC included lots of walking, lots of pho (vegetarian pho or "pho chay") at a place called Pho 24/24, not to be confused with the chain Pho 24, and lots of general exploring of the busy, chaotic streets.
2 days: Mue Ne
About a four hour bus ride from HCMC is the beach town of Mui Ne, where I decided to spend a couple of days rather than book a two-day Mekong Delta tour that I had been thinking about. Mui Ne is very walkable and consists mostly of guesthouses, tour operators, bars and cafes. While it is known as a "beach town" there is very little beach to speak of (at least where I was staying), and the water is very rough. If you like kite boarding and wind surfing this is the place to visit.
The town is also known for a few attractions, including the ferry stream and white and red sand dunes. You can easily book a package tour that lasts about three hours (in the morning or afternoon) that will combine all three. The "ferry stream" is basically a trickle of a stream you walk down while looking at some really surreal scenery, like something you might imagine finding on Mars - red sand and rock formations.
The white sand dunes are pretty spectacular and look like a vast expanse of desert - great photos to be taken here, and it's lots of fun to run down the dunes (you can also slide down them if you're so inclined). The red sand dunes weren't much compared to the white and could be skipped, in my opinion.
If you haven't booked your accommodations ahead there will be numerous touts when you get off the bus eager to show you their resort (or the one they're working for). But really, with so many options you can just walk the main street until you find a suitable spot to stay.
4 days: Dalat
A five hour bus ride from Mui Ne gets you to Dalat, a place I could have spent more time in. It's a quirky town in the hills with a very European feel also known as one of the most "romantic" spots in Vietnam. It's very popular with honeymooners and does boast its fair share of kitsch (fancy a paddle around the lake in a swan-shaped pedal boat?)
If you can, rest your head at the ultra-friendly, clean and well-located Thien An Hotel. The breakfast (included in the room price) is awesome. Fresh fruit, fresh baguettes, cheese, cold cuts, fresh squeezed juice (passion fruit when I was there) and eggs how you want them - it's a great way to start the day.
2 days: Ho Chi Minh City
Have you been to Vietnam? Where did your visit take you?