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Do a practice run

"This is so, so important," Potempa says. "Definitely -- pick your look a couple months before, and learn how to do it." And on the day of, give yourself at least an hour and a half. Allotting enough time will make sure you don't get stressed out. "Make sure you have everything out and ready, and have a clear focus on what your next steps are." Potempa says.

Also, be sure to have a backup plan. If you put on the dress, and your hair or makeup just doesn't fit the vibe you thought you were going for, it will help to have a backup look in case you decide to change your mind at the last minute, Potempa says.