How do you improve sense of humor?

A good way to become a funnier person is to hang around, or listen to people that are considered "funny". Don't copy what they do, because this would be completely unoriginal, but watch their manner and mannerisms. Another good thing to do is to act louder and larger than life, this makes people interested in you, and wanting to hear what you have to say. make whitty remarks, never laugh after you tell a joke, and never EVER say anything corny.