I think you are referring to the Double Windsor Knot or simply Windsor Knot. It is the thickest knot of all the other knot types. Here are the steps for tying the Windsor or the double Military Necktie Knot.
1: Start by Holding the wide end of tie on your right side, such that it is enlarged by a foot below the narrow end of the tie.
2. Turn the wide-end of the tie over the narrow one and bring it upwards through the loop.
3. Put the wider end down so that it comes between the loop and then cross it around the narrow end.
4. Turn it and pass it up through the loop again.
5. Slip it downwards slowly through the knot. Then tighten it. Draw it up to the collar such that you feel comfortable.
1: Start by Holding the wide end of tie on your right side, such that it is enlarged by a foot below the narrow end of the tie.
2. Turn the wide-end of the tie over the narrow one and bring it upwards through the loop.
3. Put the wider end down so that it comes between the loop and then cross it around the narrow end.
4. Turn it and pass it up through the loop again.
5. Slip it downwards slowly through the knot. Then tighten it. Draw it up to the collar such that you feel comfortable.
