Be sure to note that one side is placed on the fold and you are cutting 2 pieces. It seems like a lot of fabric, but it's a twirly skirt, so you need lots of fabric to drape and twirl up.
Stitching instructions: Pin right sides together. Stitch side seams with 1/2" seam.
Fold/Iron/Pin 1/4" hem around the bottom of the skirt. Stitch (I did a zigzag stitch to add some interest.)
Fold/Iron/Pin 1/2" seam around the waist and stitch as close to the edge as possible (so that you are leaving room for elastic. Leave 1/2" space open at the end. Work beading elastic cord through the waist (to determine the length needed, measure around the waist and subtract 1" and cut that much elastic.). Stitch last 1/2" space closed.
Hand stitch on a bow in the front, if desired.
If you want to make a matching girls twirly dress like this, I used Simplicity Pattern 2356. There were 5 different types of twirly skirt patterns included in that pattern packet.
I made my daughter and her friend matching folded flower headbands (tutorial for that to come at a later date.)