This is a tutorial showing the hand stitching on the collar of the ZW Bell Jacket, which is an optional step, but it as a great way to secure down the lining so it doesn't roll out, and it looks beautiful too! (This is step 5O, in the PDF Instruction Booklet).
This finish can be done if your lining is still rolling out slightly and is done so that the lining is not visible from the right side of the collar, or do it as a feature as this is a really beautiful detail on the underside of the collar.
Pin the OUTER collar to the LINING collar in a few places so that it is held together neatly and the collar sits nicely. Hand sew the LINING to the OUTER, going around the outer edges first, around 1.5cm / 0.5” away from the edges, with a running stitch, only lightly catching the OUTER side as you go (this stitch should not be very visible, or visible at all form the OUTER side of the collar.). Continue this stitch by spiralling it all the way into the centre of the collar with the same spacing all the way around.