How the "true believers", become aliens
First, we have the charlatan looking for some control over people, or simply trying to make some easy money. He develops some ideas from class B science fiction, of steals a few old aboriginal mythologies, like the "Star Nations" of the American Indians.
The next step is finding future followers that will believe that he, the Guru, the Contactee, the Councilor, is also the speaker in the name of those mythological Star Nations who nobody saw anywhere.
In some time, the self-proclaimed Councilor, the Wise Man, convinces some of his followers that they are star seeds but they forgot about their true Cosmic Origin.
( For a few $, the Guru will help them to memorize who they truly are.)
The "miracle" becomes true. In previously suggested fantasies, more and more "true believers" remember their original planets, their crafts and even their religions. (Of course they never remember anything scientific, but only some New Age nonsense.)
However they believe, (or not) in their fantasies, and consequently, they are now the Cosmic Nations they are looking for.
By this method and a few $$, the Cosmic Charlatans produce the inexistent Aliens. The Councilor helps the true believers or "star seeds", to "remember who they were: Aliens. These fantasies will work for some time, or will, in some cases, develop in a "multiple personality disorder".
The minor damage inflicted to the new "Aliens" is the promotion of a pathological auto-segregation from their own "just human" communities.James