... 'Cause band t-shirts aren't professional, but I needed to wear red for a school festival...
This little $4.50 caterpillar had no idea what she was destined for.
The skirt is lined with itself. Here are the two layers:
How did I do it? Easy.
Step 1: Snip the sheet above the corner seams (the part that make it a fitted sheet). Rip straight so you have a giant rectangle (this is the anger management part). Press. I like raw edges. Otherwise I'd have done something about them at this point.
Step 2: Sew the short sides of the rectangle together. (Seam 1)
Step 3: Fold the rectangle in half, almost as if you were folding the top down on a garbage bag. As you do this, be sure that the seam is to the inside and that the inner part is shorter than the outer part. Press the fold.
Step 4: Sew a top stitch about 1/8 inch from the folded edge. (Seam 2)
Step 5: Mark a line with tailor's chalk or a pencil 1 inch from your stitching line. Sew, but leave about 2 inches open. This is your casing. (Seam 3)
Step 6: Insert 3/4 inch elastic into the opening and fit. Stitch the ends together and tuck them into the casing.
Step 7: Stitch the casing closed.