Dress

Elegance. Elegance. Elegance.

It's all about the elegance. Can you tell?

Dresses - They need to be floor length. Evening dresses are floor length. Floor length. Floor length. Glad that's out of the way. No mini-dresses. No knee high dresses. This isn't a night at the club or a wedding. It's a ball. Make sure they sweep the ankles or the ground. If you take nothing else from this, take "Floor Length".
Dresses can be form-fitting if you'd like. If you just worked out for the past few months to fit into a certain dress, go for it. However, if the dress isn't flattering, don't wear it. There are many gown styles that offer soft, billowy or flowing fabrics that are very forgiving. Both styles are appropriate and look great. Go for what you feel comfortable in and what works with your body type.
Be sure to watch out for necklines that are too plunging, strapless gowns that don't stay put, and dresses that drag heavily on the ground. Also, avoid the puffy Cinderella look. Nearly all the women wear a much more modern style and you will certainly stick out. And, please, please, please, don't wear anything that even remotely resembles a wedding dress.
Be sure to pick a high quality fabric as well. The dress doesn't have to cost a mint but make sure it's not see through, spandex-like, incredibly shiny and so forth. It's worth a little more for a quality material.

Shoes - Once again, go for a formal style here. But make sure you can wear them for several hours. And remember, not only will there be before dinner drinks, pictures, and lots of walking back and forth but dancing as well. If there are a pair of heels you absolutely love but are quite uncomfortable I would recommend getting the special gel inserts for high heels. They have extra cushion and really can make a big difference. By the end of the night though, no matter what formal style you choose, expect some degree of discomfort. After so long it's bound to happen. Male dates should make sure they choose a nice-looking, classy, scuff free formal shoes as well. The Marines will be dressed to a T, so make sure you are on par.

Accessories - Depending on your situation you might need to bring along a few things. If the weather is chilly where you are consider getting a wrap. Try and find one to match your dress. There is a chance the building where the ball is could be cold as well so you might want to bring one along no matter what. Depending on who is carrying the cash/credit cards and ID's for evening you might need to bring along a clutch as well. It's the ideal size to carry just a few things. But if your Marine is willing to use his pockets that works out too. Plus, you don't have to worry about leaving your purse somewhere during the dancing portion of the evening. Jewelry is a beautiful accessory and I've seen some great pieces worn. On the other hand, many women look very elegant with none at all and the dress can really stand alone. It's up to you. Just don't go overboard and you'll be fine.

Hair, Make-up and Nails - This is such a cool event to doll up for. I know many women don't get the opportunity in their day to day life so take advantage. Get an up-do. Try long, romantic curls. Make a run to the nail salon. Feel like a pretty, pretty princess for the day. If your style is more toned down just keep it simple and refined. There are plenty of women who show up with straightened hair, basic make-up and even a swipe of clear coat or a neutral tone nail color. Whether you go all out or keep it toned down, the important thing is just to look polished and presentable.