I'm ok, I think I'm now somewhere around lvl2
I re-read TROM and have found two sentances that helped me:
(1)
Reality is the degree to which complementary postulates are created.
(2)
Communication is the action of creating complementary postulates.
So if I am black case with poor vision, and if my past objects aren't real(1) for me, that means that I have no complementary postulates with my past objects.
I took a dice from my past and have started to communicate(2) with it to make some complementary postulates.
I say "Hello to dice", then I imagined that Dice say hello to me.
That causes changes. That causes some need of RI. RI was flat before that process.
That process works for me now.