My wife and I kept up with a formula for the September 1:00 games that has worked for several seasons.

We have a couple of towels (had to be replaced this season) that were "giveaways" several years back (Winn Dixie Jaguars "terrible towels").  They were teal and had the Jaguars logo as well as a couple of other sponsors.

What we do is wet them in advance, stick them in a ziploc bag full of ice and freeze them the night before a game.  Walk into the game with them (it's allowed) and in the heat while the ice melts, the towels are cooled off.  Take one out of the ziploc if you're getting heated up and place it over your head or around you neck.  Keep in mind, you are going to get wet, but it does cool you off.

When the ice melts out of the bag, go to your friendly beverage vendor, purchase something to drink and ask them for more ice.  They will gladly fill your ziploc and you're in business for the second half of the game.

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