I have been grabbing photos here and there during the construction of the ruffs.
The top photo shows another ruff being laid out on the original pattern so that the markings for the folds can be made. Once all the circles have been marked (I think I cut 11 circles for this ruff), the next step is to thread a needle with a heavy thread- we use a button thread (Coats and Clark Dual Duty Plus) and stitch down through one mark and up through the next to accordion pleat the ruff.Tie off or wind the thread ends around a pin and then start sewing the inside edge of the ruff to the prepared neckband. You can see the stitches in the second photo. Sorry, I didn't get sewing action photos during the construction of the ruffs.
The third photo is another circular ruff we made. This one is in black linen with the same crin as a support structure. The difference here is the edge finish. This one has a piping edge, so that entails finding a fine cord - we ending up using yarn- inside a folded bias to make the piping first. The crin was stitched to one layer of the linen, then the piping was sewn to the edge, then the second layer of linen was used to "bag out" the outside edge. The tedious part of this process is the trimming and the pressing of the seam allowances along the outside edge, and then edge stitching the seam allowances down before you can join all the layers on the inside edge. You need to be careful to cut the one set of circles that form the top layer just outside your drawn line thereby making them just slightly larger, because you have to allow for the turn of the cloth taking up an incremental amount of the fabric. The piped edge does make a beautiful finished edge to the ruff, but it also adds almost a days work compared to the sewn edge finish. The bottom photo is our spiral ruff in place on the doublet. I think I may need to provide a little supportasse at the back to make sure it doesn't ever flop downwards at the back due to its size.
The ruffs are snapped to the collars of the doublets so they can be removed for dry cleaning and other maintenance such as make-up removal.
I have also made straight ruffs that had a softer fabric sewn to the inner circle to allow them to come from the inside of the doublet collar, so there can be many variations on the theme.