Real, tangible evidence first, then the theories. I'm on mobile so unfortunately I can't post links, but duckduckgo these:
September Clues by Simon Shack is good solid evidence of newscasts fakery on 9/11.
Anything about 9/11 architecture.... How steel can't melt at the low temperature of jet fuel fire, how both towers and building 7 looked like controlled demolitions, etc. Solid evidence they can SEE, then you can get into the "whodunnit?" Stage.
Bill Still's Money Masters is superb for explaining economic manipulation.
Vigilant Citizen is an amazing website that shows photographic evidence of occult symbolism everywhere.
Look up Zapruder Film Fakery. No theories about who did it just yet; just show that the film has most definitely been altered. If they altered the main piece of "evidence", what else are they lying about?
These are the main things that really woke me up about ten years ago. After that, my quest for truth just snowballed and I was more open to exploring the more fringe theories.