Generally speaking, during the hypnosis session itself, the client is invited to relax in an armchair or couch and is then guided into a state of deep physical and mental relaxation. While in hypnosis, the client is still generally aware of their surroundings and can choose to come out of hypnosis at any time. No responsible therapist would attempt to hypnotise anyone against their will, or encourage an individual to act against their natural inclinations whilst in hypnosis.
At the end of the hypnosis session, the client will be gently returned to the normal waking state. Most new clients are surprised at how far away the reality of hypnotherapy is from any prior expectation of 'mind control', and find the experience deeply relaxing.