CherryRed said:Are you referring to a little piece in the top of a sleeve, almost like a little ruffle? If so I would imagine you gather it with your sleeve and include it in the seam when you put it in the armhole. I have seen dresses with puffed sleeves that have this in the top to keep the "puffs".
What I get from the instructions, is that its' a little rectangle of stiff fabric that attaches on the inside and reinforces/stiffens the shoulder seam. I'll take a picture of the instruction sheet so you guys can see. It's pretty weird; I've never seen anything like it.