You will need:
1 pair of "Old Man Pants" that fit you (they can be a bit loose too)
Pinking Shears (optional)
Serger (if you have one)
Put the "Old Man Pants" on and mark with chalk where you'd like the bottom edge of the skirt to sit. Take the pants off and fold them in half as pictured and cut both legs off at the mark you made. Set the legs aside, you'll need them in a bit.
With a seam ripper, start to rip out the crotch seam where the four points intersect. Seam rip each inseam open and seam rip up to the bottom edge of the zipper flap. The inset photo shows you what your pants should look like when you get done seam ripping.
Pin the pockets closed, making sure that there is no puckering.
Stitch the pockets shut.
Turn the pants inside out. With pinking shears or regular scissors cut the pocket linings out of the pants. The inset shows you what the inside of the pants should look like when you complete this step.
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.
With pinking shears or regular scissors, cut the excess fabric off the rear seam and the crotch seam. Turn the skirt right side out.
With a serger or zig zag stitch, finish the bottom edge of the skirt. Set the skirt aside.
Grab one pant leg and cut off the hem. Repeat with the other pant leg.
Now measure 3 inches down from the top of the pant leg and mark with chalk. You will need to measure out four, 3 inch tall pieces. Cut. Repeat this step with the other pant leg. You should have eight, 3 inch tall pieces when you finish measuring and cutting.
Now, seam rip one side seam of one of the 3 inch tall pieces. Repeat with the other seven pieces.
Pin four of the seam ripped 3 inch tall pieces together.
Stitch the 3 inch tall pieces together to create one long fabric strip.
With a serger or zig zag stitch, finish the top and bottom edge of the long strip of fabric.
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.
Once you've cut the ruffle strips down to the length you need them, with right sides together pin the ends together to make a circle. Stitch.
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.
Stitch the bottom ruffle to the skirt, removing the pins as you sew.
Repeat step 18 with the second ruffle strip. Make sure the bottom edge of the top ruffle strip covers the top edge of the ruffle you just sewed on.
Stitch the second ruffle to the skirt, removing the pins as you sew.
Now you're finished!
Go out and snatch up every tacky plaid, striped or solid colored "Old Man Pants" you can at your local thrift store. Make an army of super cute Rock 'n' Roll Ruffle Skirts. Get creative with it and add more ruffles, or just add one ruffle to the hem. It's your choice. You could even use lace or eyelet in place of the ruffles.