So basically what I did was remove the waistband from some jean cutoffs and added a fabric tie-front waistband and matching trim around the legs. It only took about one and half hours total and a half yard of fabric. In other news, my thread did not break even once whilst sewing these babies.
So first I used a razor blade knife to remove the waistband from the cutoffs. If I would have taken my time, I probably could have "properly" removed it but whateves. It wasn't perfect but any imperfections were covered up by the fabric I added.
Then, I took the yard of fabric and folded it in half length wise and pressed it. Then I folded it over again length wise and pressed it. Then I cut along the creases into four relatively equal parts/strips. (In the next paragraph, I'll try not to start so many sentences with "Then".)
I took each strip and folded it in half and pressed. After pressing I folded each half again inwards towards the crease and pressed.
After all four strips were folded and pressed, I first pinned to the leg openings, cutting off the excess and overlapping the leg trim just slightly. Then I pinned to the waistband starting from the center back and working my way to the front. I trimmed the selvage ends off and made a little tuck on the ends, creating a triangular-shaped end.
Using a straight stitch I sewed the trim on the leg openings, folding under the overlapped portions before sewing. The waistband was next. I started from the place I started pinning from and stopped where the zipper area of the jeans started and picked up again where it stopped, stitching up the rest of the "ties".
That's it. I accidentally sewed one of the pockets into the waistband which I found out after I put them on. Big whoop, I just cut the pockets and I'll stitch it closed later.