To save yourself from embarrassment  , it's good to read a few books or research online about the culture and customs of the country you plan to visit. Clothing: Wearing shorts in public is generally not acceptable in most parts of the world, including some European countries. Greetings: Handshake is a usually accepted form of greeting, although in some countries, like Japan, a traditional bow  is preferred. Be careful how you talk with someone; don't use first names unless you are invited to do something. Language/Gestures: learn some polite expressions (hello-goodbye-thank you) and relax. English is pretty common worldwide, especially in tourist areas and you can always use body language to get your message across. However, some Americans gestures have different meanings in other countries. For example, in Bulgaria, shaking your head usually means  "yes"; shaking it "vertically" means " no". Food/Drink: you may find yourself looking down at a local delicious snake soup in china, sheep's eyes in Saudi Arabia... and wonder what to do; especially you are guests in someone's home. Be brave, take small bites, and pretend it tastes like something you like. Remember that some Buddhists don't eat beef, and Muslims don't eat pork. If you are eating with Muslims, never touch food with left hand (the left hand is for bathroom use). Conversations: if you know the history and culture of the country, you will be confident. The French are angry at the classic American question: "What do you do for a living?" and so on. A Japanese meet you for the first time, he/ she will   _  .
shake hands with you hug with you kiss you bow to you