'Occult' means 'hidden', especially in relation to mysticism and spirituality.
It can be easy to confuse the two, but hidden knowledge is not secret knowledge. The mysteries of the psychic realm are hidden in plain sight, available for everyone to look at and see they can just open their eyes for it.
Technically speaking, a psychic is a student of the occult, but that term is generally used in relation to western, more traditional and more ritualistic disciplines.
We can use dusty tomes of magic or exquisitely designed temples, but we don't need them - we all have direct access to the psychic occult right here in our minds and bodies.
Accessing the psychic occult is simply a matter of observation, application and perseverance.