There are many suitable ways to tie a necktie, including the simple style, the Half Windsor, the bow tie and the Kelvin. More adventurous options include the Elredge, the Balthus and the Trinity.
Primarily worn in China, the simple knot begins with the tie facing away from the wearer. The person making the knot places the wide end of the tie under the small end to the left, followed by moving the small end to the right. The next step is to bring the wide end up into the neck loop from underneath and then down through the loop that was just made. Tightening happens by pulling down on the wide end.
For the Half Windsor, the wide side of the tie is on the right and then moved over the small end to the left. This is then moved under the small end and to the right. The wide end should be moved up through the center, and then across the front to the right. Moving it up to the neck loop from underneath, the wearer should proceed to bring the wide end down through the loop just created. Once the tie is tightened by pulling down on the wide end, the person can slide the knot up and adjust.