The number-one rule for prom is you gotta look good, preferably sexy. And to look good, you have to get the hair and prom makeup right. We've handpicked hundreds of hairstyles for 2011 that aren't ugly, dated or wrong, wrong, wrong (tiaras, anyone? Leave that for the prom queen.
If you have a round face, then you should have hair longer than the chin and a bit longer on the neck to balance this style. Obviously, you'll need curls but if yours are in spiral be careful not to cut it too short.