This casual combo of a red and black long sleeve shirt and chinos is a tested option when you need to look casual and cool in a flash. For a more casual twist, why not add tan suede work boots to the mix? During the colder months, when practicality is top priority, it can be easy to surrender to a less-than-stylish ensemble. However, this ensemble is a striking illustration that you can actually stay warm and remain equally stylish in the colder months. This combo shows that heading into your 30s is no reason to avoid casual ensembles.