What am I forgetting? HELP PLEASE!!!?

Im in high school. This is the end of grade 11. On the last day of school, my whole school, plus a few others, go to this popular park in the city to drink and such and celebrate. This will be my third year going, but previously my clothing/ shoe choices haven't been the smartest. So this year I am thinking of wearing shorts, sneakers, knee-high socks, and a t-shirt or tank. I am going to pack flannel pj pants for when it gets cold, plus a sweatshirt, and bug spray. What else might I be forgetting?