What is pretty? It's not a definable thing. It's something that we all strive towards but few ever reach. And do you know how they reach it? They love themselves, because once you love yourself, you are invincible. That is when you become pretty, because you will never feel pretty until you love yourself.
Fashion can be a way of social identity in the community. People usually have a tendency to judge by looks, and therefore, how you dress can define how people see you. By dressing up in a way that you feel that is describing you, you give information about yourself, and attract attention of people that are similar to you. Fashion an be influenced by usually your style of music that you listen to, which can also be type of identity.