First I cut triangles out of the bottoms sides of the legs. I only meant to cut the outside bottom part, but...uh..messed up and cut both side. You could do either and it would look just fine. (Ignore my toes.)
My mom often said I was born in the wrong decade. My heart seems to be a little on the free, hippie style, with a touch of Elvis side. Next, I cut out triangles of fabric that were slightly larger than the triangles I cut out of the jeans. I hemmed the bottom of the fabric triangles.
I pinned the triangles on, although I found that it worked much better if I used a glue stick to hold the fabric in place. And yes, you read that right. A glue stick. It washes out, holds the fabric perfectly and doesn't glue up your needle. Now, it's going to be a slight pain in the ass to sew the fabric on the jeans. I used my sewing machine, but it might have save me some of my precious sanity to hand sew. I specifically decided to leave my jean edges unfinished. I wanted the rough jeaned fray look. If you prefer not to have that look, you could always sew it together to make a clean look, with all edges sewn. (Put right sides together of the fabric and the jeans and sew the edge. Repeat on the other side.)
This is what it looked like all sewn. Don't be like me - using matching thread so it doesn't stick out like a sore thumb.
Next I decided to applique some fabric on the legs. I love appliques. Now, I make my life much easier when I applique. I use Steam2Seam (Make sure you get the Steam2Seam2). With Steam2Seam you do not have to sew your edges. It is permanent and keeps your edges neat so they won't fray. I ended up stitching around the applique anyways because I like the look, but you don't have to. Admittedly, it's kind of a bitch to sew on a pant leg, but if you take your time and not afraid of a possible needle break, then go for it. I love the way it turn out.
My hippie dippy loving soul is very excited. I hope you get a chance to upcycle a pair of your jeans/pants. Send me a picture if you do!