Past life regressions can be achieved with facilitation from a certified hypnotherapist through a number of avenues. One can set an intention for following a feeling or emotion into the past to see why it is such a strong one in this lifetime. One can investigate an issue in this lifetime to see where it appeared and how you handled it in another body, place, and time.
One can move from a current situation into a past life spontaneously when the subconscious mind can see that answers to your questions lie there and not in the present lifetime. All of these and many others are options for regression.
Visiting past lives can help us understand the journey of our souls, seeing how we navigated life in other lifetimes, and gaining a greater understanding of how the soul carries connections to consciousness, values and personality.