The best thing to do around people when you dont know how to act is to just not say anything. keep your mouth shut.
My dad told me that the thing that gets you in the most trouble in life is your mouth, not what you pshysically do.
This is how rapist and serial killers get away all the time, they know how to keep their mouths shut and the ones who dont always get caught. (you know, the ones who brag) lol.
Your mouth is trouble, remember that. Just dont say anything. People are more intimidated by a quiet person than a loud person, because they dont know what to expect.
Also, they wont be able to find anything to make fun of you about because you havent said anything to them, accept the fact that you are quiet, but they dont do that.
If someone does say a stupid joke. Stare them down like you are going to kill them, or tell them straight up.
"Dont f**k with me man/girl"....then if thats the only words they heard from you, thats all they'll remember, and thats some pretty scary s**t to remember.
keep your mouth shut, because if you say..."I'm a shy person, I have asperger's, i am nopt good at social skills" that person may seem cool but he may tell a person who is not cool, or you'll get more comfortable telling just anyone who smiles.
Then that leads to rumors and so forth and they find something to pick on you about.
So just shut your mouth