I’ve vests can help some. Literally a vest with lots of pockets that you put use packs in. You can make your own, if you are so inclined. A wee bit of sewing knowledge, to add pockets to a vest, and you can use anything you can freeze into a shape that will fit in the pocket. Prebuilt ice pack. Freezer storage bag with water. Plastic water bottle, frozen. Point is, holding the ice against different parts of your skin. Polar Products makes pre-maid ice vests.

I put solid ice packs on my back or neck and use fans, and I keep a squirt bottle next to me at all times with water, spraying myself in the face when I start feeling warm. It may sound silly, but it helps. :)