Ask Me How I Know

I've been in Vietnam for 4 months, traveling eating and collecting clothes, souvenirs and more on a student's budget. I've had to learn a few things to make sure that I made the most of my limited funds and to avoid getting swindled. I hate being swindled. This is my first time abroad in any substantial capacity, and so some of these suggestions are probably obvious to seasoned travelers, but I'll list them anyway.

1. You don't have to buy things on the first day. If you can only spend a day in a city, well don't do that because you're not seeing anything that way. Chances are that many vendors have the same/better products at similar/better prices, and they are probably close by. It's funny how the rule of  'shopping around' is so easily forgotten on vacation.
2. When picking a place to eat, go to where the locals are. This is especially true of breakfast in the cities - street breakfast in Vietnam is incredible for the flavor, people watching and general cultural understanding, so don't waste the opportunity eating a 'Western' breakfast or eating out of some hotel buffet trough. The best soup of your life and a cup of tea or coffee is at most $1.75. The caveat is that you need to eat when the locals eat. Breakfast is early here (partially due to the afternoon naps), so get up on time, otherwise the food isn't as fresh, you lose the 'good meal' indicator as people go to work, and you miss the opportunity to be outside in relatively cooler weather. 
3. If a restaurant has people outside calling you in ("Hello! Come in please! Sit down!"), don't go in. They are fishing for less astute and adventurous types. Go somewhere else. [This may only apply to places on the Western tourist strips. When we've eaten at places with domestic tourists, meals have usually been great]
4. There is a fair amount of playful pushing and cajoling when it comes to purchasing items from a store or market, but if the place is really good, they know when 'no' means 'no' and won't keep hounding you to buy more. In some situations, both you and the tailor know that you actually do want and need that second fitted dress shirt, and it's okay to splurge, but never get into a situation where you feel pressured to get more. If you feel cornered, walk out and go someplace else. Leave that trap for some other sorry Westerner :) On that note, for items that require a deposit, never pay more than half. If you are friendly and can establish a good rapport, go for less, because once you pay it all, you lose your leverage. Again, pretty basic advice, but somehow easily forgotten in the heat of the moment.
5. It is okay to barter. In fact, you have to. If you're like me and are fairly non-confrontational, hopefully you have an assholeish friend that can give you the friendly backbone you need to pay prices that are fair for both you and the vendor. Visitors won't get the same price as a local, nor should they, but nobody deserves to get ripped off.
6. It is okay to buy a lame tanktop emblazoned with one of the five beer company logos. You'll look like an idiot but they are wicked cool anyway.
7. For men, wearing jeans or dress pants seems like suicide because it is so hot, but it buys you a lot of respect. There's nothing wrong with wearing baggy linen pants or Patagonia field clothes, but you stick out as what you are: a tourist. Your tattooed girlfriend, while wicked cute, also stands out. Just be wary of the kind of attention you'll attract when you label yourself a 'yobo'. If you can dress fancier, you might be mistaken for the NGO type, i.e. not a sucker.
8. Depending on the length of your trip, it is probably in your best interest to avoid Western food. There have certainly been times when I've need KFC (and it is better here than at home... the Zinger burger! ah!), but beyond that, it just isn't good here. Menus that feature Vietnamese favorites, burgers, pizzas and burritos are bloated and tacky - stick to the local food. That's why you came here, and your Italian place back home is a million times better than the Italian place here (and the Vietnamese food is a million times better than what you can get at home, duh). You'll have to make the decision for yourself if crappy nachos is better than no nachos. That said, when you can find an expat place with homestyle classics (like the Dingo Deli in Hoi An), splurge. Yesterday, I got a sandwich on ciabatta with pastrami, mango chutney, brie, lettuce and onion. Good God.
9. Lonely Planet has been completely useless except for finding accommodations. It isn't up to date, lists the most boring, polluted and pedestrian attractions, and channels all would-be explorers down the same backpacker streets, producing the same acultural experience for everyone. If you need a good American-style bar night and a hookup with a cute Belgian girl, please, give it a go, but you'll have the more 'authentic' experience by following your nose. Tripadvisor is usually more up to date and geared toward younger travelers; we used that a bit.

That's all I got so far. Going to get a late lunch.