I knew seaming my puff sleeves was going to be a challenge because the sleeve cap didn’t match the shape of the armscye. It had to be eased in. I find doing that to be a little obnoxious with sewing cloth and it sounded down right difficult with knits. To make the process easier I decided to break my sleeve up into different sections and used four seams instead of two.
I marked off the different sections of my sleeve using paper clips. The first seam went from the bottom edge to the purple markers to make the sleeve into a tube. That seam marked the bottom center. I lined that up with the bottom center of my armhole and made two seams up from the center to the green markers. That got me through seaming the shaped part of the sleeve.
I ran a piece of yarn through the top of the sleeve and used that to gather the cap until it fit the remaining length of the armscye. I used the blue center marker to line up the center top of my sleeve with the center top of my armhole. Attempting to keep my gathers even, I awkwardly sewed the thing down.
It doesn’t look too bad! I think breaking the seaming up into sections really helped. Now I just need to weave in all of the ends.