In reply to DaveH70: Assuming you going to be climbing straight-forward routes you would pretty much be happy soloing, then to be honest you can just crack on and go climbing with them. Everything will then just fall into place and you can explain things in more and more detail as the day progresses.
Provided you start easy and keep pitches/routes short, so you can communicate really easily, you can't really go too far wrong.
I always put a high priority on buddy checks and on going through the series of standard climbing calls, but for pretty much everything else I'll generally provide a bit of a running commentary and explanations as and when we do things rather than go in for long explanations beforehand.