Make a navy chambray long sleeve shirt and navy jeans your outfit choice for a laid-back menswear style with a twist. Hesitant about how to finish off? Complement this ensemble with a pair of grey athletic shoes for a more relaxed spin. There are many ways to look knockout and live through the baking hot weather, and that's one of them. And if we're talking casual style for 40-year-old guys, this getup is perfect.