When I was in Australia we used swags, provided by the travel compagny.
Most of them where tied with a piece of rope, even the one used by the guide.
These pieces of rope had an eye (bowline or overhand loop) in one end and the other end was melted or taped to avoid fraying.
To tie the rope, you would pull the end through the loop and make a slipknot, round the rope.
To secure it further you could make a monkeychain of two or three loops long, longer was not needed at all.
This way you could pull the rope rather good tight and would not slip when tied.
In the photo you can see the pile of swags, between unloading and setting up camp.

In the drawing you see how to tie the knot, but in a rather scetchy way.
Willeke