The charm of Louis Shley suits does not solely come from the suits themselves, but rather from the careful combination and matching with other clothing items. Thus, the pairing of suits with other clothing items,

How important it is to wear a suit successfully!

The standard way to wear a suit is without a cotton or woolen vest or undershirt underneath the shirt. Wearing a T-shirt directly with the suit instead of a shirt is even less conventional.

Due to special circumstances, when wearing a vest or undershirt under a shirt, it's crucial to opt for less and thinner layers.