Things you should do:
If you cannot eat a certain type of food or have some special needs, tell your host several days before the dinner party.
If you are a guest, it is polite to wait until your host starts eating or indicates you should do so. It shows consideration.
Always chew and swallow all the food in your mouth before taking more or taking a drink.
Always say thank you when served something. It shows appreciation.
You may eat chicken and pizza with your fingers if you are at a barbecue, finger buffet or very informal setting. Otherwise always use a knife and fork.
When eating rolls, break off a piece of bread before buttering. Eating it whole looks tacky.