This process varies from tradition to tradition.
In some traditions,
it is a series of meditations, including mantras,
yantras, mudras, etc.
In others,
it involves real-world experiences from several walks of life.
Overall, the goal is some form of spiritual evolution.
sourceThere are not many persons who know what wonders are opened to them in the stories and visions of their youth; for when as children we listen and dream, we think but half-formed thoughts, and when as men we try to remember, we are dulled and prosaic with the poison of life.
sourceThe valley spirit, undying
Is called the mystical female
The gateway of the mystical female
Is called the root of Heaven and Earth
It flows continuously, barely perceptible
Utilize it, it is never exhausted