Marrying a black suit with a grey gingham overcoat is an on-point choice for a classic and classy outfit. Serve a little outfit-mixing magic by sporting black leather casual boots. A practical example for any gent who's not sure how to dress as a 20-something.
Try pairing a black suit with a black crew-neck t-shirt and be prepared to be treated like a maverick in the men's fashion department. Introduce a pair of black leather casual boots to this outfit to instantly turn up the street cred of your look. A solid combo to showcase your maturity even as a 20-year-old gent.