A Half-Windsor knot is a bit smaller than a full Windsor, but it's still pretty darned big. Normal-sized people shouldn't use Half-Windsor knots except maybe as a joke.

To tie a Half-Windsor knot, drape your tie around your neck, with the fat end falling to the right. Wind the fat end half-way around the thin end, then bring it up and wind it half-way around itself. Now the fat end of the tie should be backwards on your right side. Take the fat end, wrap it around the front of the knot and bring it up, behind the knot through the "V" the tie makes at the base of your throat. Run the fat end through the loop in front of the knot and tighten.

See also Windsor knot and (my fav) the Four-in-hand knot.

This was the standard knot I used as a University of Waterloo coop student in the mid 80s. Let's see if I remember how to do this. I have a tie in hand, Here we go...

• Put tie around neck. The small end is to my left, not quite 1/4 of the tie's length is on that side.
• I cross the fat end over the small end, and then fold the fat end underneath. Now I can see the "Surrey ties" tag on the back of the fat end.
• Now I bring the fat end through the loop of cloth around my neck, from the front and out the back. The fat end is still to my right and I can still see the tag. So far, so good.
• Now I cross the fat part over the proto-knot, concealing it. The fat part comes around, behind and through the loop around my neck, on the left side. Then it goes out the front, under the knot-concealing loop and out the bottom.
• I pull it tight and Ta-da! A servicable Half-Windsor.

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