The basic idea behind the design of a choker is to accentuate the neck. In most cases this is done for reasons of sensuality. Fans of Gothic pop often use chokers as a main feature in their ensemble. The choker should fit tightly around the upper neck without becoming uncomfortable (depending upon your inclination). As a simple design, I offer the following choker for the beginning enthusiast.
Begin by making a chain three rows wide that fits tightly (but not too tightly) around the upper neck. This should clasp easily in the back. In my picture, this would be the first three rows of rings such that the As and Bs attach together. Then, in any pattern that turn you on, extend the front down to cover the lower neck. In this case, I extend the band into two dags on the ends and a main body in the center. I have left a hole in the center of the choker which sits just around the Adam's Apple. The main body ends with three dags just inches above the lower neckline of a low sweeping dress. I have added small crystals to the ends of each dag for a touch of class. For a design this large I use aluminum links so as not to weigh too heavily on the neck and leave marks (once again, you can use steel here if you are so inclined).