Show 'em what you're made of but keep it simple. If you identify some skill that is lacking, (whether technique or theory, both as crucial to improv as ear training and sight-reading) work as fast and as thoroughly as possible to fix it. Jazzy! (Don't be afraid to throw in some classical. IMO, everybody likes classical music in one way or another. More importantly, know your audience, take requests, keep it light-hearted. People enjoy seeing a musician in his element, if you're having a good time, chances are, your crowd will be enjoying it right along with you.) Also remember; you're the boss (sort of) play what you like within the taste of the audience. Just remember, if you do nothing, expect to generate no new gigs. Conduct yourself professionally. Have a rate set in your mind BEFORE any application. I once had to quit a steady restaurant gig because the owner tried to reduce my pay by half to "cut costs". Truth be told, he saw the amount of tips I was getting and decided that he didn't need to pay me. That was a very hard decision but I had to follow through. Advertise. Good luck to you! Pete