Here's how you roleplay.
For each roleplay there is a scenario and each person in roleplaying creates a character that fits within that scenario. And it's almost like a play in a way. You have your character and you write in how your character interracts with the other characters and reacts in the scenario given. If you want an example to look at , I suggest you read one of these three roleplays on the sight. They are the best examples and would be the easiest to follow. CampLocked In
The third one is a little different in the regard that the characters are premade. So the roleplayers choose a character instead of create their own:15 Days
Hope that helps. Anymore questions, just ask.