This pairing of a dark green blazer and light blue jeans is a life saver when you need to look effortlessly sleek but have no extra time. Let your outfit coordination credentials really shine by finishing this getup with a pair of desert boots. When you have one of those gloomy autumn days, sometimes only a knockout look like this one can cheer it up. So if you need dressing tips for gentlemen in their 40s, this combo is definitely worth saving for later.