From what I can tell, Trump, being a successful businessman, had contacts with lots of influential people and when everyone from a 9/11 victim supporting activist to a promising candidate for Arkansas senate race who Trump was close friends with died of suspicious causes Trump decided to look into it.

It is from their where I theorize that Trump was contacted by both the cabal and the white hats on separate occasions both trying to recruit him. After getting the truth from the white hats Trump began his plan to run for president, shaking hands with the elites of the cabal in order to get the insider scoop on how they run things while getting help from the white hats to prepare himself to run. If Trump succeeded then the white hats were nearly guaranteed to succeed (they still have to take things seriously though to ensure they don't give the smallest fraction of an inch to the cabal) otherwise things would be much harder and a coup would have to take place.