The commentors above are probably frequent viewers of /r/malefashionadvice and blindly follow the trends within. The sub is good, it has some pretty well thought out and reasoned posts with good advice, deals, etc. and if you're looking for what's in vogue for white 20-30 something skinny men then that is your place.

However being fashionable does not require you to follow a checklist of uniqlo jeans, checkered button ups, and red wings boots. Being fashionable is displaying a mastery over yourself and your image.

Proper fit, complimenting colors, understanding the style conventions of the look you're trying to go for, understanding what works and doesn't work with your body type, etc. will lead to you being able to develop your own fashion style that mirrors the person you want the world to see.

Unless you're poor. Then you're pretty limited.