Hunker.
You need to make your stall look as attrative as possible to get people to look.
The best craft fair I ever did was one leading up to christmas.
I sprayed a couple of branches silver and cemented them into huge pots which I then covered with red gingham....from the branches I hung all sorts of crafty bits I had to sell.
I bought a huge throw from a cheapy shop and used my empty storage boxes on the table to form shelves....threw the throw over the top of the boxes and the stall started to look fun and inviting because it had dimension to it....a flat table top looks boring.
If you get chance try and make up some sweet bags....cellophane from the florist....bit of ribbon...add a handfull of choccies/sweets and wrap...you can do the same with candles...make then look pretty..add a tag whatever just to make them look nice....the kidlets see sweets and drag Mom over to buy...Mom then looks at your stall instead of walking buy.
One of my best sellers is a small organza bag...the survival sack...in it you put a small eraser, a birthday candle, 1 pence piece, a marble, a small piece of string and a paper heart....if you email me at my MN user name at yahoo do co do uk I will share with you the verse that goes with this....print it on tags and tie to the bag....I made 100 of these and sold out....at 2.50 a throw I was well chuffed.
I also made up some "make them yourself" sets....5 cards, envelopes and embellishments....they sold well.
Another good one for summer sales is terracotta plant pots...a pair of gardening gloves...a few bulbs/seeds...wrap a huge hessian bow around it...add a tag and away you go...if you have time you can paint the flowerpots with a simple flower design.
I learnt very quickly that having just cards on your stall doesnt work....well not down here it didnt. IME I needed to make my stall look busy with lots of bits that people needed to stop to look at....its getting them to your stall thats the biggest battle....they see just cards so walk by unless they need a card that is.
Add your contact label to the back of your cards...Ive had many repeat orders from doing this.
HTH???
Good luck....you will be fine.