Well if you have long hair, you could wear it in high pigtails with those red ribbons tied around them. I would also wear your jewelry in red. I would definitely avoid dressing all in red though. Maybe wear a nice red shirt or t-shirt and some jeans that look really good on you and maybe some red shoes or whatever you have. What's your school's mascot? On our spirit day, me and my friends painted panther paws on our faces and did our nails in maroon and white, our school colors, and we used body paint on our arms and wrote Panthers down the side of one arm and put our class graduation date on the other one. We got a lot of compliments on our originality.

Paint yourself red. I was green and painted myself. You could also get a red t-shirt and some of that iron on transfer stuff at like, Wal-mart and design something for your class.

How about trying like red socks. Or a hat, pants, jewlery, etc...

Just make sure it matches with whatever else your wearing.