I'm going to wear a silver, sparkly Calvin Klein dress. I'm going to leave my hair down and wear a white headband. I'm not going to wear any makeup though...that's just how I roll nowadays.
I'm not looking to "wow" anyone. That's the bride's job, and maybe the bridesmaids' jobs, and other people in the wedding party's jobs.
I'm just aiming to look second-best, after all of them :)