Such must-haves as a grey plaid blazer and olive corduroy jeans are the ideal way to introduce some cool into your casual rotation. And if you need to easily step up your ensemble with a pair of shoes, why not complete your look with a pair of dark brown leather tassel loafers? As a 30-year-old gent, you want to start dressing like a grown-up. If that's the case, getups like this become a great source of inspo.