how much time prior to prom should you get your hair colored or highlighted? By zara | August 26, 2010 - 6:45 pm |August 26, 2010 What will you look like? My senior prom is in 15 days. I have dark brown hair and I really want to go blonde for prom. I need to know when is the best time to color and highlight my hair prior to prom. Thanks 🙂 Tagged best time, dark brown hair, senior prom. Bookmark the permalink.