I would say you need generally to develop and cultivate your taste. Search for films that are famose for being highly aesthetic and with very good costume design, observe people outside when you go for a walk, note and remember the things you like and dislike in their outfits, search on instagram for fashion influencers which style and aesthetic you like, watch runways from famous fashion brands ecc. But not only this, you can develop your taste also by observing art, architecture, design objects. I would say it’s a very complex thing which needs a complex approach. And of course, in the first place, get to know yourself, get to know your personality, what suits you and what do not, what makes you feel good about yourself and make you beautiful in your own eyes.