Holding a line (davids0507 touched on this).
Bent elbows, relaxed.
Double file as opposed to group? Your decision.
Verbal shorthand as opposed to taking hands off the bars ("Car up/back", "stopping/slowing", "right side"-for objects on right, etc...)

The paceline info might be more for after they have "mastered" the basics. (A multi-meeting class?)

I cover alot of this in my series on group riding. Here's the 1st of 7 posts.