If you read a big manual or a lot of instructions to role-play you will just get all confused. Just think of it this way:
Role-playing is pretending to be someone you aren't. So if you role-play as a knight, you obviously aren't going to go up to the King and say: HEY HOWS IT GOEN LAWLZ. HI KING YO.
You would have to kneel down, adress him and use words such as "Lord" and "Majesty" etc.