Some of the gals on my boxline bring spray bottles with cold water. A little spray now and then really helps cool you down! If you want to be a little Martha Stewart (or is it Steward?) about it you can add some slices of cucumber to your water bottle. At break put cold water on your arms. Wear cotton clothes or clothes that wick away the perspiration. Drink a lot of water! I am amazed at how many people I see with no water bottles (and they wonder why they are sluggish!) There are tons more tips out there so what do you do?