My chapter wore black on pref night. One chapter wore white, and all the others wore black. So, if you do choose a black dress, you may be mistaken for a sister by other PNMs. But sisters will also be wearing their badges, and their name tags will probably be a different color and/or shape.
You could accent your dress with a brightly colored scarf or wrap. You don't
need to buy a new dress. Also, if you do join a chapter that wears black for pref, you'll already have your black dress - and, regardless, what young woman doesn't need a black dress in her closet?
