As you can see, looking effortlessly classic doesn't require that much effort. Pair a black shirt jacket with white chinos and you'll look amazing. For something more on the classy side to complete your ensemble, complement this outfit with a pair of tobacco leather loafers. As the weather warms up, it's time to get rid of those bulky winter layers and opt for something lighter, like this look here. Now that's how you do smart casual as a gentleman in his thirties.