I often find one of those neck bandanas with the beads that swell up in water is useful.

I presoak it, fold it into a plastic bag, freeze it and then tuck it into a jersey pocket and break it out when needed. It is usually thawed out but still cool.

I also carry two bottles, one with electrolyte and the other with plain water so that if I get hot I can pour some over my head as needed.

I also always ride in a wicking cooler underlayer along with desoto arm coolers through most of the hot humid houston summer.

marni