I have thick and frizzy hair?

i am going out to the beach for a week and i am going to be swimming a lot. and i am getting tired of washing it and then having to wait a couple hours and then straighten it it is really thick and it takes forever to make it look nice. unfortunately we are going to be going out to dinner a lot so i have to straighten it a lot. so i was wondering if there was a hair product where my hair so just be straight or like curly for the rest of the day. or anything to make it look good without straightening it. a product where i dont have to worry about it. i have seen people have hair that looks like they just washed it and it stays like that for a really long time. HELP