If you have a look at the Pilots page in the Empire section, you will have already learned that Pilots are able to move between different realms and take stuff with them. But presumably you're here because you want to know how that works in practice?
First off, you need to actually become a Pilot. That involves being allowed access to the 'thing' that makes people into Pilots. There aren't a whole lot of those around, and they're all under the control of somebody significant.
Obviously the Empire has to have one. In fact - its got more than one - but the Guild of Pilots, headed up by the Divine Alastyr, runs them all. To get in that way, you have to sign up and agree to follow Alastyr's rules about how Pilots should behave.
The Federation has Pilots too. Unfortunately, right now it doesn't have a 'thing'. They lost it when they had a reversal of military fortunes, so right now they are not making any new Pilots.
Sable has a couple of 'things' - it also has its own Guild of Pilots that control them. Slightly less restrictive rules, but no less enthusiastically enforced.
The Reich has one. It has its own Guild too. Should I need to talk about rules and the enforcement of them in any organisation controlled by the Reich?
The Technocracy has a Guild and a 'thing'. It's not impossible to get access to this one without signing up in a Guild, but you would end up signed up to something else far less savoury. There's a man that can give you a good and fair price - honest. Lets just shake on it.
Finally - there's a Realm called Aequor, which is an undersea realm at the Aurellis end of the Inside multiverse. It has both a Guild and the requisite 'thing'.
So - now - you're a Pilot (if you survived becoming one, that is). How does it work?
Well - you need to know where you are going. In fact you need to be able to uniquely define where you are going. If there is nothing unique about a place, then how will you find it? Thusly, Pilots are in the habit of carrying around little unique markers that they can leave in places they want to get back to, that are otherwise unremarkable.
Then - you reach out with the power of Piloting to the place you wish to go, and instantly (or actually in about 6 seconds) haul yourself and the stuff you are carrying through to that place, providing the place you want to arrive has the space for you to arrive in, passing through none of the intervening space or realms.
But you do pass through something, and that something is generally fatal to non-Pilots unless they are in specially shielded transport vehicles that the Guilds provide for the purpose. Obviously, there's a few variables about that - strong flexible people can stand unshielded transits within the same realm with little harm. Really strong really flexible people can often stand unshielded hops between nearby realms and only get severely ill. But the base rule is that if you're not a Pilot, you need to be in a shielded transport vehicle to safely travel via Piloting.