I've been working on a list of things that are important to know if you're going to attempt to blend into Bulgarian culture...
[DISCLAIMER: We've only been here 2 months, so some of these may be overgeneralized!]
Never put your purse on the floor.
If it's the first day of school, take your teacher a flower.
If you go "out for coffee" be prepared to stay for at least 2 hours.
Don't drink out of the bottle! Use a glass!
At home, where the most comfortable clothes you have - sweatpants, old t-shirts, etc. When you go out, dress up! (Even if it's just a quick run to the store.)
Alternate who pays when you go out with friends.
If you are getting out a piece of gum, always offer a piece to everyone else.
Always order at least a drink when you are at a cafe.
Speak quietly when in public.
Warn other cars that there is a police man checking speeds by flashing your lights.
Don't rush when shopping, or when doing anything, really.
When eating out with friends, offer a taste of your food.
When a car is passing you on the road, pull to the right as far as possible so they can get back over as soon as possible.
Greet people (shop-keepers, friends, family) with the appropriate "good morning," "good day," or "good evening" when you enter a room.
If you've made plans with someone, you should confirm them again directly before the actual event.
If see a car with a flat tire, you should point it out to the driver.
Don't push through a line, just wait your turn.
When paying, generally you put the money on the counter. Do not hand it to the cashier directly.
