motivation or explanation that motivates

Hey, I've been trying to shift my reality for maybe SIX YEARS and no, I still haven't managed it. I go back to it every now and then during the year so I don't get obsessed, but I'd love to experience it. The thing is, in the middle of any method, my head starts wondering how it's even possible to change realities, and I don't know if it's demotivation or just the overwhelming doubt of not knowing, but it ruins my whole approach and I just can't do it. So if anyone who has already done it would like to or can explain how it really works, it would be a huge help. Peace <3