A yellow crew-neck t-shirt and black skinny jeans are awesome menswear elements to have in your current casual wardrobe. When not sure as to the footwear, go with black athletic shoes. Men who are curious how to pull off modern casual outfits after 30, you have your answer.
For a look that's very straightforward but can be manipulated in many different ways, consider teaming a yellow crew-neck t-shirt with black skinny jeans. Take a classier approach with footwear and introduce mustard suede espadrilles to the mix. This ensemble illustrates how young men slay in the fashion department.