My natural tendency is toward formal wear... suits, vests, ties, dress shirts, slacks, loafers, peacoats, fedoras, etc.
Unfortunately it's difficult for me to maintain that style very long while binding, especially in warmer weather. So I tend to just wear shorts, flipflops and T-shirts - at least during summer. Thankfully in winter I can actually hide my chest with layers and jackets and look formal without even binding, in most cases.