I think this is a fantastic guide. Probably the best resource I've seen for men's fashion, actually.
I want to add this:
The Concept Wardrobe for Inverted Triangles
This guide is about the Inverted Triangle, a common male body shape, but is aimed at feminizing that body type's appearance. But I think what holds true for this body type, even for a masculine appearance, is that wider trousers look amazing. Harry Styles has rocked flared, bell bottom trousers.