If you are in search of the perfect evening dress, you need to consider your size, body type, and style. The trick is to find a dress that compliments you so that you can look great no matter how small or large you are. You need to determine your body shape: pear, hourglass, athletic, apple, or thin, and then base your search for an evening dress accordingly.
If you have a pear shaped body, your best bet is an a-line dress, as it will accentuate your top and cover your bottom. Make sure that the right areas will be enhanced, though, or the dress won't look flattering at all. Wear a v-shaped dress if you have an apple body shape. This type of evening dress is designed to draw attention to the bust area, just as long as you avoid long sleeves.
There are quite a few styles that look great on hourglass figures. A dress with a scooped neck line, for instance, will flatter your bust and make you appear taller. You can also go with a full-length gown with an accentuated waistline. Just don't go overboard with laces or ruffles, as they will hide your curves. You will want to enhance all your assets, not hide them!
If you have an athletic or boyish figure, your choice of evening dress should have details that will soften your shoulders and add to your bust line. 
The top part of the dress should have ruffles or lace, and the bottom should have a tulip shape. You could also get away with wearing an a-line dress if you are wider. Choose something with a lot of details such as flowers, polka dots, or other feminine designs.
Once you have an idea of what type of evening dress you need to get to flatter your body shape, you need to choose a color and design. They come in all colors and shades, and you need to choose something that looks great with your skin tone. You don't want to wear something too bold, but you don't want your look to be subdued, either. If the evening dress doesn't fit right, it will only make matters worse if you wear the wrong color.
You can also wear some accessories for a more flattering look. Dresses look impressive and lovely when adorned with the right accessories. The right pair of shoes, for instance, will enhance your overall look with the evening dress. However, you need to choose the right color and fabric to match the dress. Also wear a matching necklace, bracelet, and earrings. As long as everything matches your evening dress, you will look great!