This idea is not a new one and there are plenty of tuts and varying methods, this is the way I do it.

Take an old pair of old jeans that you can still fit at the waist but don’t wear anymore, because of worn knees for example.

Cut about 2-3cm longer than you want the length of skirt to be. You need to allow for a hem if you are having one and a bit extra for realigning the edge.
This one I cut even shorter after I took the photo as I am going to put a ruffle on the bottom.

Unpick leg seams and about half the crotch seams, to where the seam straightens out.

Open and lay the flaps over each other, pin.
Open cut off leg piece,

insert under opening and pin together.

Sew the insert stitching in the centre of the original seam allowance, and zig zag the cut edges if you want.

This is what it will look like underneath

Cut away the excess up to 1cm away from the seam.

I like to put an extra row of zig zag stitch where the original seam was, one, to reinforce if this area is worn, and two, to stop the underneath insert panel edge from fraying.

Do the same with the back.
Hem the skirt if you want, or leave to fray.
I decided to add a frill on the bottom.
I joined strips of leftover denim to make a large circle, almost twice the width of the skirt’s bottom edge.

I added some gathered tulle and a strip of floral printed cotton to the denim strip and attached to to the bottom of the skirt, gathering as I went.
This is the finished result:

Here’s another one I prepared earlier. This one has a double row of stitching at the hem so it doesn’t fray too far. It will look more “raggy” after a wash and tumble dry.

Note the zig zag stitching on the overlap. The fabric had worn thin on this pair and it needed some reinforcement. I also put a patch underneath on the back

I made this about two years ago, from an old pair of jeans that I didn’t wear anymore. I was inspired by some original looking skirts I saw online made from jeans combined with other fabrics and decided to have a go at the jeans to skirt transformation myself.

There are many sites out there with tutorials that will show you how to turn jeans into a skirt with some slight variations, basically you cut the legs to the length required, cut or unpick the inner leg seams up to the crotch, then a little bit further up the front and back seams, overlap the top bits so they sit flat and then stitch in a triangle panel to fill in the gap. You can also cut up the side seams if you wish and insert panels for extra flare at the sides.

For more details check out Busy Parents online or this site with instructions from five other websites, or try this video if you like more visual instructions.

For my skirt, I decided lots of flowers up one side would be something different and add a bit of personality.

I made some patterns in varying sizes of my chosen motif – a five petal flower, and chose some red scrap fabrics with differing textures – plain cotton, printed, velvet and satin to make the flowers.

I appliqued some of the flower shapes onto the skirt  and used others to make floating shapes to layer on top for a more textured look.

Some of the flowers were attached by sewing white flower and red seed beads in the centre and others were attached by sewing on some red tulle roses that I had made for another project many years ago.

I enjoy wearing my one of kind skirt to different occasions, and it certainly gets noticed!