Now some of you may be too young to remember the contrasting collared dress shirt back in the 1980's . There is now a rebirth of this shirt. Aaron Marino of alpha m. shows a great way to accessorize and utilize the contrasting collared dress shirt.
The shirt is bit elevated in the dressiness department; therefore, the French cuff is appropriate. You can also pull of the shirt without a suit. Where do you get one? Local department stores are an option, but selection is minimal. Modern Tailor is the best bet for fit and customization.