Instead of tying a sweater around the waste, I’d suggest putting the waste in a Hefty trash bag. It’s sturdier and easier to dispose of:
Here’s Ms. Jenner with her waste-enshrouding sweater, courtesy of Yahoo! Style:
I’m no fashion expert — unlike the writers for Style — but it looks like Ms. Jenner’s sweater is wrapped around an area of her body just below her waist. But I’m no fashion expert.