I'm running a game where the PCs discover that they're actually Fae. Obviously this isn't strictly canonical - Fae in CtL leave fetches in place of children, not their own young - but I'm otherwise trying to stay with the source material as much as possible.
The book says that "the human mind [...] seems intrinsically incapable of comprehending the vast paradoxical nature of [Fairie]", but as True Fae the PCs should be able to understand it a lot better. So, how do I describe the world such that the PCs can function there while still conveying something that the players themselves should be incapable of comprehending?
This seems like a terrible idea, but I like to push the boundaries and see what I can make work.
In the end the PCs fortunately didn't spend too much time in the Fae world, but for when they were there I mostly just ran it as Equinox Road describes for mortals (which is considerably less paradoxical than the core book suggests), but explaining the basic rules of a realm as they became relevant rather than leaving them to work those things out for themselves. Also, only one of them ever truly shed his mortal form and doing so left title-less and trapped in the (surprisingly ill-described) weakened actor form, which meant it always made sense that they saw things from am much more mortal-based perspective anyway.
Possibly I kind of wussed out on the idea a little bit by keeping them grounded that way, but the 'True Fae in Faerie' was never the goal of the campaign; it was more an eventuality I wanted to be prepared for if it came up. The players all said they enjoyed the campaign though, so I call that a win.