i cut 3 layers a fabric: 2 strength layers of cotton ticking and 1 fashion layer of a thin stretch fabric. this ended up being 48 pieces total.
i used the marked strength layers with seam allowance to cut the stretch layer. i decided on the using it as a fashion layer to cover the boning so it was less visible in the end, as well as visual cohesion with the other costume pieces.
thus begins the combining into 3 layers, leaving front completely open and backs mostly open where the lacing will go.
i also added waist tape to the inside of 1 strength layer, tacked in place, then combined the 2 strength layers together. boning channels were added as a sandwich between layers along each seam.
tacking the fashion layer on was more complicated. it was pinned on, then tacked at waist (avoiding the boning channels). i finalized and sewed along the bottom seam to combine all 3 layers.
with the fashion layer mostly on it was time to finish the front by adding the zipper. its a heavy duty metal non separating zipper that had to be shortened, then basted and sewn to each side. i then used elastic binding for the bottom of that seam and its counterpart, and added hook/eye to have a removable seam.
with this all together it was time to add boning. I used heavy duty 10mm plastic cable ties, cut to size and rounded edges. because these come curved, I also used my iron (plus pressing cloth) to straighten before adding. i ended up also going back into the seams with the iron so I could bend the bones around my boobs for a more appropriate silhouette.
this meant i could finish closing all seams to create 1 garment. i edge bound the legs in elastic for fit, and top edges with 1in cotton tape. this was done with a combination of hand and machine sewing. i then marked and added grommets in my usual fashion, added lacing and was able to put the entire thing on.
this is meant to be worn with laces completely closed and basically no waist reduction for comfort and to hopefully increase wearability.
and with that we have a base layer strong enough to build upon and inform the shapes of the rest of the garment