How do I put back the spring into the rubber around the drum? ?

Exactly where to fit the spring in the inner part of the rubber, the one that goes to the drum? There are several folds in the rubber, once I fit the spring into the one I think is correct, it simply snaps out.
One end of the rubber connects to the drum and I have to attach a spring around the rubber, into one of the folds...I don't know which one is the correct.
The other end of the rubber goes to the front part of the machine, where the door closes. No problem there.
It is driving me crazy, I would really appreciate your help.
It is a Thor TL1 500 washing machine.
Thanks a lot