Personnally, first area I get way too hot is my head. So it needs something that air can go through easily.

I tried different helmets and I had been told that the Catlikes are the ones I would probably prefer the best for this. Not the nicest looking ones, but they do amazing job and are super light.

So I waited for my LBS to have their 50% annual sale and purchased one. One of the best moves (sports related) I did. I rode with it and never once did my face flush from overheating. My head remains cool. I also purchased the bug net that you put inside. Luckily, my shop only carried the white so I was not "forced" to get a colour I would not have liked.

http://www.catlike.es/us/en/helmets/...d/R0150012SVR/

For me, having tons of holes helped immensely in keeping my head cooler.