What should I wear to a cookout?

So i am having a cookout tonight with all my friends and I dont know what to wear! I want to look cute but not like i am trying to hard to look cute when i am just hanging out. I dont have many options cuz i havent done my summer shopping yet, but its kinda chilly. I am thinking about jeans with a purple HM dress that i have but I dont know how to accessorize it... thanks in advance for any ideas you have!