We all look for practicality when it comes to fashion, and this street style pairing of a grey hoodie and black sweatpants is a great example of that. All you need is a pair of grey athletic shoes to finish this outfit. Can you see how super easy it is to look stylish and stay snug when cooler weather arrives, all thanks to outfits like this one? And if we're talking casualwear for 20-year-old guys, this ensemble is ideal.