Have you ever been told to cover your mouth when you sneeze? Did you wonder why? Well, the reason that you cover your mouth when you sneeze, is to avoid spreading germs. Another reason we cover our mouths when we sneeze is because it is polite. When you sneeze it is polite to turn your head away from the people near you.
Did you know that it is not polite to burp without saying excuse me? On the other hand, in India it is considered a compliment to burp at the table. If you do not burp at the table you are insulting the cook's food. This is also true in Japan. In many countries it is very rude not to try some of everything that is offered to you. In some countries you sit on a mat on the floor and your table is a small coffee table in front of you. When you are eating you always chew with your mouth closed and you never talk with your mouth full. Never read or watch television if you have a guest, or if you are having a family meal. When you are finished eating you say excuse me and wait for permission to leave the table. This rule also applies if you need to go to the restroom or if you need to get by someone.
When you ask someone to pass you something you always say please and thank you. This rule also applies when you ask someone for help to do something. If someone asks you to do something and then thanks you, always tell them that they are welcome.
Never interrupt a conversation. Either tap the person on the shoulder and wait for them, or wait nearby for them to notice you. When you are indoors never raise your voice in order to talk to someone. If you cannot be heard, wait and say what you have to say later.
A rule of thumb is that the gentlemen always remove their hats when they enter a building. Ladies, on the other hand, may leave their hats on anywhere they are. Ladies never do their makeup or their hair at the table or in the kitchen. Always go into the bathroom or into the bedroom to fix those little niceties. Never blow your nose in public if you can avoid it. Excuse yourself and go into a seperate room, preferably a bathroom.
If you are cooking for a large group of people be sure to pin your hair up so that none of it gets into the food. If you can remember and apply these rules of conduct to your life, they will help you on your way.
I think this is more pertinent to etiquette, decorum, and cultural differences around the world that help with maintaining a polite lifestyle.