For an off-duty outfit, pair a dark green long sleeve shirt with brown chinos — these items go really well together. And if you want to instantly dial up your outfit with shoes, why not choose a pair of brown suede casual boots? So so as you can see, it's an on-trend, not to mention spring-ready, outfit to keep in your seasonal sartorial collection. Casual ensembles for 20-something guys aren't actually that hard, as you see here.