I moved your topic over to the right place for you.
The short answer is that they do the same thing as everyone else. They create characters, learn and use skills as well as participate in the story of the weekend per normal. The only exception to this is in the combat scenarios they cannot strike or be struck physically. There are detailed rules about interacting with non-combat characters in our online rulebook that explain how damage and skills apply to such players. You may want to look into that if you are curious.
Also, take a look at our forum rules. You must put at least part of your real name (for example in your signature) when you post on these boards. You do /not/ need to put your full name as after all this is the internet. It is a commonly missed thing for new posters.
Let us know if you have any other questions though. We are here to help.