(ps the note editor function isn't working for me so i'm sorry in advance for the lack of notes)
Step 1: Materials/Tools
More than enough elastic the thicker the better as long as it fits (at least 500mm/2' more than you need). (I doubled mine up as it was all i could find).
1 pair of Vice Grips.
A Knife/ Leatherman.
10 Minutes of your time.
Step 2: Remove the old elastic
Arrange the poles in the order that they came apart all facing the same way. This is to make it easy to put back together.
Step 3: Tie and thread
remember that we arranged the tent poles? now you see exactly why.
Here's a trick that i used to make things easier simply use some of your old elastic or some thin wire if you have some handy to thread your new elastic through the individual pieces.