This relaxed casual combo of a denim jacket and a v-neck t-shirt is a foolproof option when you need to look stylish in a flash. Get a bit experimental in the shoe department and dial down this ensemble by sporting a pair of tan high top sneakers. Can you see how very easy it is to look sharp and stay toasty when chillier weather hits, all thanks to ensembles like this? When it comes to casual style for 30-something men, this combination is perfect.