I'm going camping and it gets hot, what should I wear?

I mean material wise, my friends say cotton but this is some rough camping and I want it to be durable. Should I wear polyester blends or cotton or all polyester? I need something durable, cool, and doesn't mind getting wet. Also what type of socks/underwear should I wear? Boxers, briefs? Tube socks, crew cuts? ( I will be wearing boots ) I've been told it gets in the 90's and 100's. Please help me with what you know!