Effortlessly blurring the line between cool and casual, this pairing of a black puffer coat and a white long sleeve shirt will easily become your go-to. Got bored with this outfit? Introduce a pair of black leather derby shoes to jazz things up. When you have one of those dreary autumn days, sometimes only a cool getup like this one can brighten it up. So if you're searching for a stylish and mature getup for a 20-something guy, look no further.