Couple of suggestions whilst picking the outfit:
This day isn't about you.
Do not wear white or anything too closely to it.
Stay classy. You can never go wrong. Don't go crazy experimenting.
Determine the difference between sexy and skanky.
Of coarse I wouldn't just say this without examples!
Calvin Klein on sale right now actually for $64.99
McQ Zipper Shift Dress from Intermix $365
Alice + Olivia Cara Cap Sleeve Sequin $440