I can give you a tip from the point of view one among the stream of Joe Public who walks past numerous buskers every day. Be entertaining and good humoured. Smile a lot. Lift people's day a bit. And don't, at all costs, be yet another Bob Dylan clone doggedly strumming a small collection of chords and sing songs which are vaguely about the meaning of life. Busking, remember, is a branch of showbusiness.

Good luck.