For an off-duty look, wear a grey crew-neck t-shirt with khaki chinos — these two items go nicely together. Throw in a pair of white canvas low top sneakers and you're all set looking smashing. As you can see here, this getup is a really nice idea, especially for transeasonal weather, when the temperature is dropping. This combination demonstrates how to keep killing it in the casual fashion department as a 40-year-old man.