This pairing of a navy blazer and a grey dress shirt is a real life saver when you need to look casually sleek but have no time. For something more on the daring side to round off this look, choose a pair of white canvas low top sneakers. As you can see, it's super easy to look awesome and stay comfy when cooler weather hits, thanks to this outfit. So if you need dressing tips for gentlemen in their 30s, this ensemble is perfect.