hm, i dont know if you will understand this but i'll give it a shot:
first i would start out with how people were doing the tshirt skirts over the summer. i dont know if you were around then or recall but what they were doing was cutting right under the arms of a tank top, tshirt, etc.
then sew, turn right side out....essentially you are making what would be similar to a tube top. follow?
then i would cut your tulle. hmm. probably three sets of varying lengths, or four, or however many layers you want. the examples appear to have longer ones at the bottom, shorter at the top.
after you have your tulle cut, i would begin sewing to the bottom of your skirt, i.e. tube top. begin with your longest layer, stitch by hand and pull to scrunch like you were mentioning. do this all the way around. then repeat with the next layer, and so forth.
ah....im tired so i dont know if you understand what i mean...but i think that should help get you going.