Take fishing line to strengthen banner to the sides of the tent. I love my banner but it has only three grommets on the top. It tends to sag so I tie the top and bottom to the sides of the tent. This year I took picture wire for that but it could puncture the sides.
I also, never thought about grounding the grommets on the bottom of the tent sides. The sides were billowing in and out. I tried mini bungee cords, but even the minis wouldn't go through the grommets. That's how I hurt myself trying to put a bungee hook into the folded over part of the bungee. Needless to say it doesn't work. I wired these to the stabilizer bars but again it could puncture the tent. Next year I need to bring stakes or figure out some "safe" way to attach the walls to secure them.
We had water to drink but needed water to clean the silver after I dunked it in the silver cleaner. Never fear........ I was in Fountain Park. Voila! Instant water to rinse off the cleaner. Note to self....... next year take water expressly for that purpose (or not.) I will probably have to take it to other shows that don't have a fountain near by.
All in all, these are about the only things I needed and didn't have. With set up the day before the festival it was easy enough to get what we needed. ( I got the bungees........ a waste of money.) It's best though to have these things ahead of time.
AppleFest is pretty level (except for an occasional tree root.) Other places may not be as level. So I made note a long time ago that a variety of wood pieces would be good to have to level the tent. I saw some pretty hilly set ups at the Penn State Festival and saw how the artists coped with it.