After sewing up the lining seams, I measured a certain amount down from the waistline. The fullness had to start a little below the hips. After marking with pins, I used the longest machine stitch to mark the line. I did this at the hip and also 15" up from the hem as there are 2 flounces to attach.
I cut out 4 panels of net, each one @ 32" long for the main flounce and 4 panels of net (14" long) for the bottom flounce. The panels for each section were sewn together to make a tube. The "marked lines" on the lining (both sets) were divided into 4 sections also. A large basting stitch was sewn across the top of the net panels on both sets. It's easiest to work in sections so each set of basting threads started and ended with a panel. The top of the panel was pinned - beginning and end to the lining section and using the basting thread, drawn up to fit into the space. Then using pins every inch, I pinned like crazy to hold the gathered net to the lining.
I have to say...working with net was the "the pits", full of static when attaching to a synthetic lining and all over the place and quite prickly! I kept thinking through this whole process, I'm glad no one in the family ever wanted to be a ballerina and I had to make costumes. Anyway, if I ever entertain the notion of working with net again - Just Shoot Me! What started out in my mind as a simple job, turned into a whole day affair, but it's over and done and looks pretty good. (Isn't that ridiculous! below)
I sewed the net in place with a narrow zigzag stitch. One of the things that really helped in handling all this net was the little tool you see below.
One of my students gave it to me years ago and I cherish it. I've found more ways to use it and working with it here it was a great. It held the net so the needle could catch where I wanted it to.