A grey crew-neck sweater and black chinos are absolute menswear must-haves that will integrate really well within your off-duty styling arsenal. Unimpressed with this outfit? Introduce white leather low top sneakers to switch things up. This one is a viable choice when it comes to figuring out a kick-ass outfit for summer-to-fall weather. As you're transitioning from your 20s to your 30s, you want to start dressing like an adult man. That's when combinations like this become very relevant.