Go find the biggest guy in your school/work and either get some brass knuckles or wrap a small bit of chain around your hand. Next go up to him when there is lots of people around and stick him in the face as hard as you can. One of 2 things will happen he will either go down, in which case you you hit him 2-3 more times so every one gets the message. Now if he doesn't go down you really gotta start firing on him and let him really have it once he goes down make sure hes good and down. Once you have sent your message to him look at everyone else and say, "Who else doesn't wanna be my friend?"