According to wikipedia

Hypnosis is normally preceded by a “hypnotic induction” technique. Traditionally this was interpreted as a method of putting the subject into a “hypnotic trance”; however subsequent “nonstate” theorists have viewed it differently, as a means of heightening client expectation, defining their role, focusing attention, etc. There are an enormous variety of different induction techniques used in hypnotism. However, by far the most influential method was the original “eye-fixation” technique of Braid, also known as “Braidism”. Many variations of the eye-fixation approach exist, including the induction used in the Stanford Hypnotic Susceptibility Scale (SHSS), the most widely-used research tool in the field of hypnotism. Braid’s original description of his induction is as follows: