I always appreciate a man with a fine wardrobe and a good personal sense of style. At the same time, I'm glad I have neither. Stained loafers, mismatched socks, dockers, and a t shirt that you've recently dried your hands on work just as well with a flat cap. In fact, the flat cap imparts style to what I generally refer to as extreme casual clothing. The criterion for being extreme casual is whether you sleep in the clothes that you also conduct your daily affairs in. Changing socks and underwear daily is permissible.