It's best to learn from other psions, but if you can't find any then it will be a bit more difficult. There are books and websites about learning psionics, one example is psipog.net (link below).
Complete Psionic was created in 2006.
Tristan Psionic was created in 1992.
Tristan Psionic ended in 2010.
Complete Psionic has 160 pages.
The Sounds of Tristan Psionic was created in 1919-12.
Psionic Artifacts of Athas was created in 1996.
Mind the Gap - Tristan Psionic album - was created on 2000-04-18.
Practice, practice practice! You can usually google good ways to practice.
Protoss are psionic. They do not require speech to communicate. They draw nourishment from their psi pylons, and thus have no need to eat. Because the protoss communicate telepathically, as they are psionic. Therefore they have no need for ouths to speak. I'm sure they hadmouths once, but they evolved so they no longer have them. As for ears, i have no idea how they hear, as not all terran and zerg have psionic abilities.
Are there peculiar ways different cultures or nationalities practice their faith?
There only seems to be three ways i.e. practice, practice, practice, practice
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