Don't be afraid of making an ass of yourself.

Everything you do, everything, everything you say, do, write or express doesn't have to be smart, inteligent, well analysed and thought through. Say "fart" just to see how the people around you react. Be silly and crazy. Let go of steam. Sure people will say you are childish. But then again - that is not your problem. There are some very heavy stuff in life. But not everything have to be it.