How good should you be? I mean how much experience?
I don't think it comes down to how "good" you are. It is more about how entertaining you are. I am a magician who has been working in the same restaurant for about a year now. I've worked othere...and I'm not saying that a year is a long time. But for a franchise such as the one I'm in, it is a pretty long time. Anyway, with that said...there is a whole lot more to entertaining as a magician and just performing great tricks to someone in a restaurant. When I go from table to table performing, I quickly build rapport (sp) with the people of that table. I'm actually scoping the table out as I approach. I'm not really, really old, but I'm a little older than some of the posters here. I have a family. I have three kids ranging form 2 and a half to 7 yrs of age. So if I'm approaching a table with kids or even a baby, I immediately start talking about their kids and my kids, etc. People love to answer questions about their kids such as:
How old is she/he? Is she small for her age?
Just different things like that. If you are younger and have younger brothers or sisters, you could apply the same type of approach.
Another thing I commonly do is ask if they are from around here. And any time you can make a joke out of something (non-insulting of course), then do so. The more you can make them laugh, the more entertaining you will be. You pretty much have to be a comedian and a magician. That's very important. And you have to be very outgoing. If that doesn't come natural for you, some good practice would be to approach total strangers in public areas (not restrooms) and start talking to them and show them a few tricks. You could call it "Blaining" or whatever, but don't try to be like him. Be yourself and find your own style and personality.
Back to your question. It can't be about how much experience because until you have done a restaurant or other paid venues, you have no experience...only practice. keep practicing. When you are completely comfortable with your routine, and communicating with total strangers effectively, then you might be ready. Don't enen consider you are until then.