A couple other folks have already given us their technique for making this oft-used, but often overlooked, piece of gear, the ubiquitous bungee cord.
Here's a step by step.
All you need is needle nose pliers, some hair ties, flexible wire, and a lighter.
Once you cut the hair tie, melt the ends to keep them from unraveling.
Cut two pieces of wire, approximately 2 inches long.
Bend the wire so that 1/3 is on one end, and 2/3 on the other end.