Another alternative is that they sell little cargo nets, which are like a bungee net with multiple hooks that you can use to hold the stuff on better.
If you have nothing else but bungees etc, the trick is to put them on in a way that they are snug, and that they hold your cargo against shifting side to side, and fore to aft.
__________________
Slow Ride Cyclists of NEPA
People do not seem to realize that their opinion of the world is also a confession of character.
- Ralph Waldo Emerson