Posted 7/27/2014 11:03 PM (GMT 0)
100% cotton comes to mind, first. Then, there are those bandana-type of cooling neck scarves that, when dampened, keep one cooler.
I just did a quick search on "clothing to keep you cool" and "items in clothing to keep you cool" and lots of items came up. There are even some name brand clothing items for this, such as "Chill Factor."
Hope this helps a bit. Heat and humidity are miserable. I find the sleeveless cotton shifts are comfy, too.
Best wishes! :)