before you go out on stage, put yourself in the place of the audience. think about the fact that if you were in the audience and you made a mistake, or were terrible, you would forget about it in about four days, and you wouldn't mention it to the bad person anyway. also you can not look at the audience, but at a spot at the back of the room, but dont trail off, stay focused to what your doing! also take a four second deep breath, hold it for eight seconds, and then let it go for four seconds.
Well they say imagine people in their underwear but it didn't work for me. What I tried to do was keep my focus above people's heads. You can't help but hear them, but looking just above people's heads isn't distracting to them and you don't really see them.