The idea come to me when I was unpacking newly bought clothes. Some how those new clothes, when you open up the packing, there's this tracing paper placed when they fold the clothes. So when I was taking it out, the tracing paper made so much noise when crushing or just folding it.
So I though of sticking the tracing paper on to the plastic layer of the diaper. And there!! You get a super crinkling diaper that make so much noise and lasts for so long.