I used a sleeve pattern I made a while back for the green Carpi gown. The lining is cut to a fitting size, and the velvet is cut two times as wide and three times as tall.
I then marked three evenly space lines from side to side on both the lining and the velvet. On the lining, I cut three strips of bias tape to the correct, finished width.
Again, I kept my stitches as invisible as possible, running the majority of my thread between the layers to keep it hidden. I started the stitch lines about an inch from the edges so that I would still have wiggle room to finish the seam.