For those with quadriplegia and our friends with other health conditions requiring extra caution during heat advisories, please see these tips.
I love handy fact sheets that explain things. Here are other tips I learned over the years. Feel free to add yours in the comments.
To cool down quickly, wrap ice cubes in a towel and place around your neck - or just use ice cubes! Use a mister. Carry a frozen bottle of water with you so you can place it against your body - and drink it too.