One
You're 13 years old and someone gives you a copy of The Secret by Rhonda Byrne. You ferociously read the pages and absorb all it's content and even though it's a cute feel good read - you realise it isn't enough to just "know" about manifestation, you decide that you want to decide to figure out how it works.
Two
So you fun an experiment with the sole goal of wowing your parents with your GCSE results. You write down A*s on every flat surface, you visualise standing in the hall on results day, and you mentally obsess about this goal. You don't finish school with all the A*'s that you hoped but you get close (6 A's 2 b's a 1 c close). Nonetheless achieving this result is enough to prove to you that you in fact - created this result with your mind.