The first thing to understand is that hypnosis is not sleep- the hypnotised person remains fully conscious. In fact, it’s part of my job to stop the client from dropping off to sleep, even though they’re as physically relaxed as if they were asleep.
Hypnosis is an altered state of consciousness, in which the mind is opened to suggestion. There are many ways to induce hypnosis but most involve focusing the client’s attention in different ways. Some methods involve the hypnotist touching or lifting the client’s hand or arm, but no other physical contact is needed.