I love to do vendor shows I find they make me more relaxed. The customers come to you so all you have to do is practice your 30 second commercial and sell sell sell. They are interested in your product they stopped at your table half the battle has been won. Victory for you now all you have to do is close the deal.
You need to ask questions before you commit to any event first and foremost how much will it cost you. Remember spending more does not mean you will have better sales. I have paid $20 and done very well and paid $75 and sold nothing. So you can't judge by the amount you spend.
Advertising- you need to find out what the event holder is doing. Make sure they are not just hoping that the participates will do the advertising. We know word of mouth is a very powerful so by all means talk up your event. Offer something special to your customers for stopping by.
Offer a drawing for free product use your contact cards they will fill it out and there you go new contacts. Remember* call them or email ask them there preferred method of contact and follow up. They were interested enough in your product to want some free use that as a lead in to holding a show.
I would love to hear what has worked for you any suggestions you may have......