Maybe treat it as a tablecloth, to drape, so to speak, and model it upside down. Mindful that the dangling portion will need to be cinched up, or gathered. Now, I am thinking that you may approach this like modeling a teardrop. That suggests that you could start with a basic Sketchup UV sphere or a Geodesic sphere as one element, extend it, or stretch it, or scale it upward, form a 2d profile resembling gathered fabric, progressively/ sequentially pushpull and scale for a "few" reps, then tie a rope around it when you get tired. That's probably what I would try, without getting into plugins.