I agree with the two posts above, and was going to recommend a black cocktail dress with killer black shoes. You can never go wrong with that. You might want to add a great accessory to make the outfit yours-sparkly earrings, an amazing clutch purse, a bright red wrap, etc. (depending on the style of your dress) Like Teresa said, make sure you own your look, and be confident about the outfit you choose to wear-if you do that, you'll give off a great vibe
Have a great time!