Effortlessly blurring the line between sharp and casual, this pairing of an olive turtleneck and dark green chinos is sure to become one of your go-tos. You could stick to a more casual route on the shoe front by rocking a pair of olive athletic shoes. On not so cold afternoons, you can sport this summer-to-autumn look and look absolutely amazing. This combination illustrates that going from your 20s to your 30s is no reason to shed casual style altogether.