Or if you're asking what the character is physically doing when they transfer the curse, well, we don't even know what they were doing when they cast it the first time. We know they said something, because of the verbal component, but that's clearly not all they were doing, because the other party members can't just say the same word and get their own Hex. They're also tapping into their emotions, or remembering the bond they made with their patron, or doing something that only a spellcaster can do, and that's something aside from the outward, physical manifestation of the components.

Well, whatever extra thing it was that they did to cast the spell, they're doing that same thing again to transfer it. But without the magic words this time, because it didn't say you need those.