I think the idea is to set the "I will trust you if you do x"

and then set X as a threshold sufficiently high that if they do all the necessary things to even be able to accomplish X then you will trust them. Or make X impossible.

Assign X as a fuzzy thing, like "treat me like a human being" so that they can't just buy you an apple and "gain your trust".

(for me, anyway, trust is not consciously given, so.)