The final stage of K's dress was finishing the main upper layer - basically identical to the satin lining but with an asymetrical hemline adaptation (tapering from upper thigh to floor), wider skirt to accomodate the net underlayers & the addition of a tulle hemline edging.
At an earlier fitting of the demi-toile, a hemline guide had been marked for this layer & when finally cut out, it was made slightly longer than necessary. At its first fitting, this additional length was needed since the volume of net changed the visible proportions of it.
The edge was first overlocked & then 2 separate rows of stay stitching were made – one along the overlocked edge & the other along the intended hem foldline (appx. 0.3"/0.7cm) to prevent any undue stretching.
When turned along this stay-stitched edge (above - close-up showing overlocked & stitched edge) ...
... it was again machine stitched appx. 0.25"/0.5cm from the edge – this providing a good stable hemline to next have the finishing attached.
For the final fitting, the 2 lining layers were stitched together (the net layers were only safety-pinned to verify movement of the dress in wear) so that the main dress could be fitted over it to confirm all final shapings. "Randomly scrunching" the tulle skirt, confirmed the placement & shape of the hemline edging as well as verifying how the skirt would be finished: a length of randomly scrunched tulle attached along the edge of the hemline (see below).
Both of these finishings were completed with the dress on its hanger - below images of the dress in its final stages, front (left) & back (right) views