Okay, 100 years ago you either wore cotton, wool, leather or silk. Since only the very wealthy living in big cities could afford or even find silk clothing, guess what everyone had to wear to stay cool back then?

If cotton is all you got, then you make the best of it. Personally I think hemp makes a better fabric, but the process is a little more involved, and right now it is a bit too difficult getting permission to grow any here.