Turn your jeans inside out, and fold them in half along the center of the back / butt. Then draw a straight line from the center belt loop to the bottom of the pants. Pin them and sew along that line. I used a hem stitch. You might want to put a denim needle in your sewing machine.
Next cut off the excess fabric, fold it over, and hem stitch the raw edges down. I made sure to stitch over the first stitches so as not to make the skirt even tighter.
Take a large piece of paper (I used a leaf lawn bag) and lay it inside of the skirt. Lay out the front of the skirt how you want the center panel to be. Then trace around the edges.
Add at least a half of an inch around the traced edge for seam allowance then cut out your pattern. Pin your fabric to the paper and cut it out. You can look at the post from yesterday to see how I picked out my fabric. Sometimes seeing a picture of it vs in person gives a nice perspective on what you would like more. Next fold and sew the raw edges of your fabric towards the right side of the fabric.
Insert your fabric into the skirt and pin it in place. Then sew it using a hem stitch (I'm referring to the same stitch that is used on t-shirts).
I had a hole on one of the knees of my jeans. So I stitched over the hole several times. Then I used a cute iron on patch to cover it. I just so happened to have a matching patch in my house, which is weird since I don't usually buy them.
Next cut off the bottom seams on your jeans. They are to hard to sew over. Then roll and sew the new bottom hem of your skirt.