There are a few practical tactics to follow:
Bring a bunch of plastic grocery bags (if your state/county still allows them) or a couple of canvas totes. You'd be amazed at how many sellers in the members' halls don't have bags for you to carry your purchases.
I used to say "bring a bunch - like $40 worth - of singles." Prices for the little things you see and realize you need are now in the $5 range, so...bring $100 in small bills, along with your allowance.
Remember where you parked. If you buy a few heavy items, go back to your car (keep it locked) and drop off the first round of items you bought. Then go back into the fray.
There's an ATM (maybe two ? ) on the grounds, in case you blow through the $3000.00 allowance you brought with you. It traditionally runs out of cash early.
Wear old shoes that don't hurt. No one will criticize your old "dad shoes."
Like the other guys mentioned: If you see something you want/need either put a deposit on it and come back to get it later, or pay in full and take it to your car. Don't figure on making a mental note of the hall, aisle and table, and then come back to buy it. It won't be there.
If it's been really sunny, and you want to drink a nice cup of fresh-squeezed lemonade from one of the vendors, and it's been sitting in the sun for a while, opt for a can of soda. I speak from experience.
And finally, no crop dusting, please.
