Help! I want a new look for highschool?

I want to change up my look for highschool. I'm 5ft. Athletic build greenish grey eyes and medium brown hair. I'd like to grow out my hair long but I'm not sure what color I want to dye my hair. Any tips? I think I want it darker but what do you guys think. Also any tips about going into highschool. I'm not a nerd or anything I'm pretty outgoing and make friends easily I am also a cheerleader.