I've made a ton of these super cute ruffle skirts. They are really simple to make and the best part is that you'll be making them out of thrifted clothing. Just hit up the men's trouser section at your local thrift store and find the tackiest pair you can find. Don't worry, they won't be tacky for long!
Fold the pants in half so that the outside leg seams of the pants are lined up and touching on the inside. From the upper rear seam, draw a line with chalk straight down to the hem of the skirt and then pin. From the bottom of the zipper flap, draw a line in chalk straight down to the hem of the skirt and pin.
Now stitch along the lines you drew in step 6. This closes up the seams that you ripped out and now you have a skirt. Try the skirt on to see if you need to take more in. If so, take more in using the rear seam. Simply redraw the line and restitch. TIP: To make sure you don't get any seam bulges, find the original seam stitching and start your stitching from there.
Fold 1/4 inch of the top edge of the long fabric strip over to make a hem. Pin. Stitch. Repeat with the lower edge. Repeat with the second long fabric strip. These hemmed strips will become the ruffles of the skirt. Now lay your skirt out flat and measure the bottom edge. Take that measurement and times it by 2, then add 13 inches to it. This is how long your ruffle strips need to be. Measure the ruffle strips and cut them down to this measurement if needs be.
Find the seam you just sewed in step 17. Line that seam of the ruffle strip up with the rear center seam (making sure the wrong side of the ruffle strip is facing the right side of the skirt). Pin. Now, every 2 inches fold over half an inch and pin. Continue to pin until you reach the front of the skirt. This technique gathers the ruffle strip, making ruffles.