I know at some grocery stores here you get blue elastics with some vegetables you can use those the same way by folding them. Also for the longest time I had a large bag of elastics from the dollar store, also had to fold then, but they worked the same way. One step I did different from this guy's walkthrough was to place the elastic on the screwdriver when trying to get it through the center/crouch piece as sometimes the elastic wouldn't stay together.

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