We dress up when we go out to feel good about ourselves and to attract the attention of guys. We know that guys will look and check us out. However, if the guy stares for too long then we get uncomfortable. Why? Literally, some girls might feel like he is undressing her with his eyes and it can be uncomfortable. It's one thing to check a girl out, it's another to REALLY stare a long time.
When girls dress up, it's almost like an immediate confidence boost. If we look good, we feel good. Some girls are just insecure, so that may be why the nervous side is apparent, it's nothing personal.
i read about this somewhere , actually a lot of the reason for dressing up is to compete with other attractive girls for attention and such , I read that's what a lot of it is about , especially in places like trendy night clubs wear they dress up , its more to be pretty or be better looking than that other girl . its not necessary to get a guys attention . from what I read there is a lot more going on with girls when they do stuff like this and dress up than us guys really clue into .