There are three ways to tie that knot.
Different knots go with different collars.
For instance, the half and full Windsors tend to be bulky, and look good only under larger or spread collars, which are in fashion. But the Windsor knots themselves are passe. When wearing it under the spread collar, loosen the knot a little so that it is larger, but not sloppy. Versatile enough for button-down collars, too. At any rate, the secret to a well-tied tie is in mastering the knot you choose.