Here's a simple idea that may inspire you. Next time you find a terrific deal on a skirt, purchase two, instead of one.
Buy the first skirt in your size...
and the second one a bit larger.
Cut the top off the larger skirt and iron under the raw edges, pin to the bottom of a matching color slip. Try on the under skirt, with the over skirt. Make sure you like the length, that the two balance well together. ~*~ For the underskirt, sew the top of the lower skirt fabric onto the bottom of the slip, attaching the two together. Make sure the slip fits snugly around your waist (as the skirt fabric will add weight). If you need to make your slip fit more snugly, simply take in the sides seems of the waist (right sides together). Worn together, these two skirts create one stylish look~
(The skirts above, were purchased at TJ Max last year for $16~ each).