If your dress is sweet, soft, and long it is best to choose something classical. You want the hair to be more polished and sleek. When you are wearing a strapless dress it is best to opt for a more romantic look. You should try something with a flexible curl or lightly pinned up. Don't be shy of the pin up, just because you do not have the length doesn't mean you cannot work with the short hair you do have. And when you have a dress that is a little flirty and fun, make sure your short hairstyle is mimicking the same sassiness.
