You can't rehearse

Either you're interested, or you’re not. The fashion world isn't for everyone, and personal style can't be defined or judged. But to those who feel like I do, the only way to begin is to jump in with both feet. To start with, decide what you like, and what repulses you. Occasionally there is an in-between in how you feel about a piece, but maybe you're just not analyzing enough. Designers tend to have a style they continue throughout all their lines, so do your research, and choose your top three.

Six Designers who are well known and have made an impression in the fashion world (you need to know this):
       Kate Spade
       Anne Sui
       Tommy Hilfiger
       Ralph Lauren
       Betsy Johnson
       Vera Wang

If you don't know at least three of these names...I'm concerned on why you're interested in fashion to begin with.

Things you need to know about being interested in this world:
You will be judged on your style (since you're an expert and all...). People will ask your advice. You need to be critically honest about how something looks on someone, and give them other options. You need to do your research and stay up with the trends. You need to remember you're not a runway model, so therefore you don't need to wear a fur coat and thigh-high boots every day. You need to be determined and keep with your beliefs; don’t let the critics get to you.  

You are you, know your style, and embrace it.