For a safe classic and casual option, you can't go wrong with this pairing of a crew-neck sweater and a light blue dress shirt.
Light Blue Dress Shirt with Crew-neck Sweater Outfits For Men
This smart combination of a crew-neck sweater and a light blue dress shirt is very easy to put together in next to no time, helping you look awesome and prepared for anything without spending too much time going through your wardrobe.