Just dress how you feel best represents you! The point of pride isn't only to have pride in being queer, but to have pride in yourself overall, so just wear what you're comfortable in :) I have similar hair as yours, and I like to put it on the top of my head in a knot bun or dutch/french braid it when it's hot out.
Maybe do your hair in some sort of nice updo. You could do something besides the traditional ponytail. Maybe like Elsa's coronation hairdo. And as for the outfit. Shorts would be fine. They don't have to be booty shorts if you're not comfortable with it. Though I'm sure if you did wear them you wouldn't be the only one. ^_^ And a regular tank top or tshirt would work. And also wear sneakers or flip flops. Do not wear heels or fancy sandals. Your feet will hurt like a s.o.b