Read through r/malefashionadvice and their wiki, they have a bunch of info on how to improve your style. Specifically, they have threads every day called What Are You Wearing Today which has people take pictures of themselves and what they're wearing specifically (brands, name of clothing SKU) which you can then pick up to buy if you like it, or find alternatives for it.

https://www.reddit.com/r/malefashionadvice/wiki

Start reading fashion magazines and tear out the pictures of stuff you like. Then when you see something you like at the mall or Macy's, get it. If there's stuff in your closet you don't wear (or don't like to wear), fold it and put it in storage and if you haven't needed it for 6-12 months, give it away and replace it with a garment of the same type that you like.