Jeremiah,
I have done about 10 gun shows and they can be good places to sell. You need to have alot of business cards, a sample of stamps or border patterns you can customize items with, alot of belts striped out, key fobs cut out, and cell phone cases cut out. I know you are going to a gun show but I will be willing to bet you will stay busy making belts and cell phone holders if you plan to do it on the spot like I do. I would have a good display of several items like a cartridge belt if you have time that always brings alot of attention. I would have holsters for the following guns: pocket holsters for the keltec .380, / Ruger LCP, Some IWB for Glocks, a few 1911's, a few small frame revolvers, a few pocket holsters for the small .22's, a few western styles for 6" revolvers. You need to have a few of the items you plan to sell cut out and ready for stain and tooling, being able to make items in front of the customer really generates a crowd and equals more sells. I would also find me a nice looking lady to go with me and watch the table when you're busy hahahahah! ..but it works. Find a rebel flag stamp you will need it and stamp your initials on a few of the holsters for display. You will take alot of orders so have you an order form with all the needed information on it ready for them to fill out.