(especially for bow ties) is to form a loop at one of the ends of the initial half-hitch, and circle it with the other end, which is simultaneously folded into a second loop that is then pushed through the knot.
* The quickest approach is said to be one involving making one loop between the thumb and forefinger of each hand, and pulling each loop through the other; speed probably requires acquisition of muscle memory via repetition that is guided by a sequence of images.

More secure shoe-tying knots