Some Cayce quotes to get you started:
In the soul or psychic experience one attunes the God-self to the universal! Hence the application or experience is from within and in communion with the influence of God-force in the individual life. (165-24)
Psychic is of the soul, then, first becoming aware of its inactivity or activity toward the Creator within thine own experience. Not as from without; for the external experiences will be the natural result when the self is attuned. (261-15)
(Q) Is this entity one who may properly now pursue the higher and inner development of its soul and psychic forces?
(A) It is, as has been indicated. And in the development of the psychic forces, of the psychic influences and powers in the experience, enter into the Holy of holies, cleansing the mind, the body, in whatsoever way and manner as prepareth or bespeaketh to thee that thou mayest present thyself in body and mind as being CLEAN and ready for the acceptance of that the Lord, thy God, may give thee in the way of directions. (442-3)
(Q) What must she do that she may develop her psychic abilities?
(A) Psychic is of the soul; the abilities to reason BY the faculties or by the mind of the soul. And when this is done, enter into the inner self, opening self through the ideals of the meditation that have been presented through these channels, and surrounding self with the consciousness of the Christ that He may guide in that as will be shown thee; either in writing (inspirationally, not hand guided) or in the intuitive forces that come from the deeper meditation, may there come much that would guide self first. Do not seek first the material things, but rather spiritual guidance, developing self to the attunement to the psychic forces of the spheres as through the experiences in the varied activities in the varied planes of experience, but ever in the light of that promise that has been given to be known among men, "If ye love me, keep my commandments, that I may come and abide with thee and bring to thy remembrance those things that thou hast need of that have been BETWEEN me and thee since the foundations of the world!" (513-1)
But, as understood - or should be by each soul, the development must be SELF-development, SOUL development. That the psychic faculties of a soul or entity are the manners through which manifestations may come from the outside and from within, is the experience of most individuals in their development; though they may call such manifestations by many names, that are seen or given under various lines of thought or various manners of development. Yet these expressions or manifestations are, as we would give, of the soul or the psychic faculties of the soul, or soul or spirit world. (440-8)
(Q) Please give a definition of psychic phenomena.
(A) PSYCHIC means of the SPIRIT or SOUL, for cooperation of the Phenomena, or manifestation of the workings of those forces within the individual, or through the individual, from whom such phenomena, or of such phases of the working of the spirit and soul, to bring the actions of these to the physical plane, Phenomena meaning only the act itself, brought to the attention, or manifested in such a way as to bring the attention of an individual to the work itself. Psychic in the broader sense meaning spirit, soul, or the imagination of the mind, when attuned to the various phases of either of these two portions of the entity of an individual, or from the entity of others who are passed into the other planes than the physical or material; yet in the broader sense, the Phenomena of Psychic forces is as material as the forces that become visible to the material or physical plane. Psychic forces cover many various conditions, depending upon the development of the individual, or how far distant the entity is from the plane of spirit and soul forces. PSYCHIC means not understood from the physical, or material, or conscious mind. PSYCHIC means that of the mind presenting the soul and the spirit entity as manifested in the individual mind. Then taking the phases of that force, we find all Psychic Phenomena or force, presented through one of the acknowledged five senses of the physical or material body, - these being used as the mode of manifesting to individuals. Hence we would have in the truest sense, PSYCHIC, meaning the expression to the material world of the latent, or hidden sense of the soul and spirit forces, whether manifested from behind, or in and through the material plane…
(Q) How many kinds of Psychic Phenomena are known to mankind at the present time?
(A) Almost as many as there are individuals, each entity being a force, or world within itself. Those of the unseen forces become then the knowledge of the individual, the power of expression, or of giving the knowledge obtained, being of an individual matter.
(Q) Why do women usually show more interest in Psychic matters than men do?
(A) For their minds, women are filled, or left vacant for the study of spiritual forces more than men, for the same reason as we have given. What their minds fill or feed upon for development toward Psychic forces comes from the subconscious or the spirit and soul minds. (3744-2)
As for how the entity may develop its own psychic or soul faculties, this is the interpretation of the psychic force: That the ideals of the soul may shine through and give that which may be helpful in the experience, and in reaching and in gaining that which is as the material manifestation in the fruitage of that sown as the seed of life in the soul of that individual. Then, in developing same, that there may come the greater awakening: Prepare self to be that channel through which there may come those things in the experiences of others that may bring the greater blessings to them, by aiding most those that are able to turn back into the records of those that need the knowledge and help that may come, whether for the body, for the mind, for the spiritual influences. (295-9)