Guided Imagery: All hypnosis is self-hypnosis; you control how deep you want to go. On a depth scale of 1 to 6, Guided Imagery is 1-2, the lightest states. But even there, much can be accomplished!
Hypnosis: The feeling is very similar to meditation; a state of relaxed focus. The difference is that while meditation quiets and empties the mind, hypnosis fills the mind with thoughts and images directed toward the changes you want to make in your life.
Regression: This very deep level of hypnosis allows you to re-live past events in order to challenge existing behaviors and move forward. Also used to access past life experiences.