First public event.

For displaying the rocks and cabs you might consider in the future using some wooden trays lined with some kind of fabric of your choosing - doesn't have to be velvet. Be a bit creative with it and use the folds of the fabric to help display each stone and cab. Your trays look to have some kind of lining but your stones look like they are in very close contact to each other. Use more trays and spread them out and have them down lower so people see them better. If your trays are all laid out at waist level on your table all the stones are able to be seen and more shopable.

I use a tray for what few small cabs I sell that has a glass top on it. This is great for shows where I'm the only person manning my booth. I don't always have help and any deterrent to five finger discounts I can use is fine with me.

For displaying your earrings, I too like how you use the cards over the wire. However you might want to use a uniform card color. A uniform color gives things a more polished look.

When I was at the Canandaigua Arts Festival a month ago a woman nearby was also selling jewelry. She had made all her own earrings cards using card stock and she had applied velcro to the back of the cards and had them hanging from velcro tapes. Her cards were all a uniform off-white and she had hand stamped her logo on the top of each. It looked very professional.

I buy premade blank black display cards flocked with velvet as they go with my black velvet display stands and black suedecloth tablecloth.