Several months ago when Hubby was cleaning out his closet, he put a bunch of sweaters in a pile to donate. I quickly snapped them up and they have languished in my sewing room ever since. It was time, homeys.
I am, of course, seemingly always in the process of cleaning out my sewing room and finishing unfinished projects (ostensibly so I can start something new).
You need, of course, a sweater and a pillow form. Wash the sweater in hot water and dry on high. Turn the sweater inside out and lay flat. Lay the pillow form on the sweater to get a general idea of how the two will fit together. You do not want to cut before you start sewing.
Step one is to sew across the midsection. In this case, I also sewed new seams on the sides as my pillow form was skinnier than my sweater. AFTER you sew, then you can cut off the upper part of the sweater.
I think if you are truly industrious, you can probably find a use for the remainder of the sweater. Like if you have a much nicer midsection than I do, you could probably just wear it over a cami frayed ends and all, or stuff and sew it closed for a draft snake...but I digress.
You are probably also noticing the puckering in the sewing in the photo below. We'll get to that in a moment.This closeup is to show that I do a straight stitch and then a wide zigzag as well directly over it for strength.