Intro: Pencil Skirts
Here are a couple of very easy jean pencil skirts that I made. I used inner tubes for trim. I have the full instructions here: http://instructables.com/id/Easy-Skirts-From-Clothing-Ties-and-inner-tubes/ and here: http://instructables.com/id/Easy-Pencil-Skirt-With-Inner-Tube-Trim/
All you need is one bicycle inner tube, a pair of jeans, basic sewing tools, a sewing machine, a skirt that fits for a pattern and your set to go. Trim the inner leg and cut out the shorts. Cut the bottom of the skirt the length plus the hem you want. Trim the shorts seams on the side so you have 2 pieces. Place the inner tube between the layers of the front panels and sew the bottom of the skirt to the shorts front. Sew the back shorts to the bottom of the skirt. Sew the sides allowing enough room on the hem for a slit on one side. Hem the bottom.