How to improve my closet/clothing/style?

I like to describe my style as sort of a vintage/classy girl esque...like, if any of you have watched Pretty Little Liars, well, I'd describe my style as 75% Spencer's, and 25% Aria's...if that makes since. I love floral patterns, and when I get back to school, I wanna look approachable, I'm switching schools again. Any fashion advice, stores, what to buy, tips, tricks or tweaks are helpful :D Thanks!