If you're scouting for a contemporary but also stylish outfit, try pairing a navy open cardigan with a white crew-neck t-shirt. If you wish to immediately step up this ensemble with footwear, add white canvas slip-on sneakers to the mix. With spring in the air, it's time to make space for simple and on-trend combos, just like this one. Those who are curious how to wear modern casual looks as you head into your 30s, this pairing should answer your question.