The seven-fold method is a technique for the production of the traditional necktie. It is applicable exclusively to hand-made, low-production lines due to the attention that is required to employ it, and it is believed by many to form the original -- and most elegant -- sort of modern cravat.
Due to the realities of contemporary garment production, most neckties nowadays are made very differently than they were in the heyday of the seven-fold tie. Usually, they are crafted from a small cut of silk or polyester interfaced with a woolen core by an acetate sheet. This process is cheap, and simple enough to be done by a machine (although it is often done by hand in the case of finer pieces). The creation of a seven-fold tie is a bit more demanding. It is hardly a marvel of engineering -- but it cannot be done efficiently without human dexterity. A whole square yard of fabric (always silk by example, though not necessarily in principle) is folded upon itself, seven times, precisely as the title suggests -- three times over the front of the central panel (what would otherwise be the core of the tie), and four times over the back. Then, the loose lip of fabric is stitched into the layer before it, and it is labeled and finished as any other tie.
Before electronic machinery was ever used to make clothing, and neck ties were always made by hand, the seven-fold method was frequently used. Only two major designer companies make seven-fold ties anymore -- those are Italian fashion house Kiton, and the American clothier Robert Talbott. Kiton and Talbott ties usually retail for upwards of $200. They have a fluid flexibility and drape that seldom lends itself to cored ties -- which is why the seven-fold method is still used at all.