Dee's advice is what I used for the most part. If you give your mind the chance to talk you out of it, your mind will probably talk you out of it. Just go.
Another thing to keep in mind is C.I.Q. Compliment. Introduction. Question. Walk up to someone, say something like, "You're looking lovely tonight. My name is *Name*, I'm a performer. Can I show you something?" Not that exactly but something structured like that.
It's really important, as a performer, to develop social skills. The ability to small talk is invaluable. It makes people comfortable around you. If people are comfortable around you, they are more likely to think of you when they need a performer. I recommend learning to talk to strangers. It's not hard, just say hi and ask how they're day is.