What are some good summer hairstyles?

I live in a very hot and humid place, so this summer I don't want to use any heat on my hair (straighteners, etc). I have naturally wavy and frizzy hair, so I can't just wear it natural and have it look good. It's also a bit hard to manage because it is really thick. I sometimes scrunch my hair, but I'm going to have to start waking up early to go to classes so I don't want to have to wet my hair in the morning. I also sometimes just put it up in a messy bun, but I am tired of that. What are some easy hairstyles that don't require heat and will work on my hair?