Fold your bandana in half and cut along the fold to get two equal pieces.
Put the bandana pieces right sides together, with the cut edges on the top. Pin and sew a 1/4" seam down both sides.
Fold the cut edge over 1/4" and press it with an iron. Fold it again about 3/4" and press again. This will be the casing for your elastic.
Sew around the top of the skirt, close to the bottom of the fold. Leave an opening a couple of inches wide to thread your elastic through later.
With your skirt still inside out, pin and sew the eyelet lace trim to the bottom.
When you get to the ends, trim and fold the raw edges under.
Put a safety pin through one end of the elastic and use it to help you thread the elastic through the casing. Sew the ends together with your sewing machine and then sew the opening closed.
Turn the skirt right side out to finish.