This semi-casual combo of a white dress shirt and navy jeans is super easy to pull together in no time flat, helping you look seriously stylish and prepared for anything without spending a ton of time going through your wardrobe. On the shoe front, go for something on the classier end of the spectrum by rounding off with dark brown leather brogues. Wondering how to dress appropriately for your age as you get into your 30s? This ensemble is a great illustration.