How can I possibly add style to this strict dresscode?

Work you hair and shoes. Your hair can be any way you want it to beso go for it. I don't know if it is allowed but wear neat headbands and stuff. If i was you I would do my hair different everyday, and find cool styles. You shoes probably have to be a certain color so get many differnt styles of shoes. Since you don't have to buy back to school clothes, if you can, spend some money onj the shoes. Try to also wear a different pair of shoes everyday to make you outfit different from everyones. I hope this information is good for you. Good luck!