A small project from scrap knit. I cut out a half circle skirt according to my waist circumpherence.
I sewed the sides on both the skirt and the rubber band and pinned it by halves together.
I used a technique that I'd learned on boxer shorts - I sew WRONG sides together, like a centimeter from the edge of the rubber band, then I fold the skirt panel down and add one more line of stitches at the very edge of the band. Of course pulling the rubber band a lot so that the seam is stretchy.
The fabric was so nice, dense and super lightweight, that I didn't hem the lower edge.