The basic concept for using a medium to divine goes way back to the shamanistic practice of reading the entrails or interpreting sign. The fact that the reader must have some perceptive insight working before the medium was found has been underplayed by the mainstream users of the adopted systems, Tarot, Rune, Tea Leaves, Palms and crystal balls to mention most of the mainstream favourites.
The original shamanists that used their ability for the group did make a point of not being tied to a particular system, knowing that they would have to initiate their spontaneous reasoning faculty to affect the insight from anything that might reflect the macrocosms take on the microcosms event. So instigating the inspirational system would be a must and so the reliance on a specific system would be seen as a limiting of the faculty.
Rather than teach any potential acolyte, that’s someone showing the talents and displaying an interest in the mysteries. Teach them the creative spontaneity of divining the moment. Rather than guessing the outcome through a complex medium. Read the moment, its mood, attitude and its intentions to keep the eye on the ball. A sort of forensic eye on the probable outcomes and lay a course for the outcome of your choice. Or the edge of your perceptions from insights highest point.
When the acolyte can make accurate predictions in a regular fashion then advancement is achieved. After a while the faculty can exceed any mere medium.
The five elements that have to be taken into account are the nature of the trap, because vision is so beguiling it makes us all focus on the external image of the moment, but when we internalise our concentration then the inner senses start to relay information, no not true that is when we first become aware of something that is already happening inside us, it is just brought into our inner perceptions focus of consciousness.
The acolyte will sense impressions, feelings, time and probable actions. With the eyes closed the collective consciousness will relay impressions to the focus of the locus, the concentration of mind, body, emotions and spirit that go to make up the locus of being.
Reading fortunes is a fairground attraction and is just the right level of expected platitudes for the pence.
Develop the faculty, practice in the moment and learn to know, then know well ahead and that should take care of the predictive illusion in a single sentence.
Just keep practicing and just guess to begin with and work out your odds to see how many punters you can fool before they see through you.
For all those that actually have the talent you should have the wisdom to believe in yourself and have the faith to know the certainty in the read. And of course the last but not the least by a long chalk the passion will ignite the power and release the inner phoenix of transformation.