As much cash and as many credit/debit cards as you can fit in your wallet!!!
Lots of stuff for sale, and you are bound to find just about anything you might desire.
Arrows for trying bows - Yes!!
Camera - Yes!!
Your own bow - no, they don't allow bows to be carried around. Those that want to sell a used bow check them in at a table near the entrance where they can be sold on consignement.
It is warm inside, so once you are in the doors there is no need for warm clothing.
Plenty of chairs available for the seminars.
Bag for carrying stuff - Yes!! I've seen guys wearing backpacks too, and that works great.