If you don't take fashion too seriously, go for a bold casual outfit in a tank and navy jeans. Tap into some Ryan Gosling dapperness and introduce navy canvas slip-on sneakers to your outfit. Relaxed outfits for guys in their 40s aren't actually that hard, as you can see here.
A tank and navy jeans will add serious cool to your day-to-day off-duty wardrobe. When not sure about the footwear, choose a pair of dark green canvas high top sneakers. This outfit is a big inspiration to anyone who wasn't sure about dressing casually after forty.