I've done festivals where I've sold hand stamped cards and gift things, like handmade baby bibs. Its important to have your booth look nice to attract people. Have a great display, a nice table cloth. Lots
for them to look at. You want people to stop and really have to look through your booth, cause other people will see the first people looking and thing "Hey, there are a lot of people over there. It must be good stuff. Let's look!"
Definitely have tags made for your items. What I did was just to make business cards, and to use them as tags I punched a hole and attached with thread or yarn. Use some for tags and some as business cards to pass out, and you don't have to make 2 different items. If you're comfortable with the computer, you can just buy the precut business card sheets and do them yourself. You can also use cardstock from the scrapbook store if you want nice colors of paper. Then just cut to the size you want.
Keep us updated on what you decide to do. I love going to these festivals. Maybe I'll have to come check you out!
(And bring some baby bibs to sell! I have lots! LOL!)