That's exactly how you do it.
I used to work for a Kimber dealer and have some experience with doing this. 8TC is a little more complicated than the others but basically the same. You will want to carefully unwind the ends and spread the conductors apart. The aim is to have just enough length to be able to seperate the postive (blue) and negative (black) and be able to selectively reaggregate them to their respective bundles, ideally without having either side with a stray strand over the other.
As for once the ends are separated, yes just twist the two bundles. you do not 'braid' the wires ar the ends. (once the plus and minus are separated, braiding has no known benefits, aside from appearance. most just twist the bundles up to the connectors.
(I HAVE 8TC in my stereo and surround systems)