Hypnosis is a state that most resembles the moment between being asleep and awake. It is one of the most effective states to connect with our senses without language. 

A person is always in control of what happens to them during hypnosis. Often the hypnotist with ask questions and the client will answer. 

No. Sometimes it takes more practice to keep a trance stable. 

A desire to change, willingness to look for deeper causes, and regular practice.