The knot should stay snug on top of the collar button. A tie that is too tight will creep up the collar, not too mention reddening your face and making it difficult to breathe! A loosened tie looks sloppy and is a sign that you are not paying attention.

2torial #0538: Learn2 Tie a Bowtie (Continued) Set the stage   Shirt on? Collar buttoned? Put the bowtie around your neck, seams to the inside. Let the widening point on your nondominant side hang down from the collar button by your collarbone (so if you're left-handed, lay it on the right side). The other side should be an inch or two longer. Hold the spot just above the widening point with your nondominant hand between thumb and forefinger. This spot is where you'll tie the knot. Step 4