Psychic healing is an ability a psychic can develop.
There are three basic ways psychic healing can be used: healing oneself, helping others heal themselves, and healing others.
Healing oneself is the first psychic healing ability to practice. Even if one is already healthy, since we change with each moment in our lives, the process of psychic healing is crucial to being whole.
Helping others heal themselves is a psychic healing process that is less draining for the psychic and in the long term more beneficial to the person being healed. Since the psychic observes things other don't normally notice, communicating these observations to others can be very useful in prevention as well as actual healing.
Healing others directly is a process that is exhausting (and potentially dangerous) for the psychic, and more beneficial in the short term for the person being healed.