I was gifted some denim rectangles, and used some of them with some dark denim offcuts of my own to sew an unlined Patchwork Denim jacket. All the denim was stretch denim, though the percentage stretch varied a bit.
The jacket is based on the cardigan jacket from New Look 6082.
I made 8 sections of patchwork slightly larger than the corresponding pattern piece, sewing long columns of the denim rectangles first, and then overlocking those seams. Once the columns were complete I then sewed them together to create the patchwork piece, and overlocked those seams. Once each panel was completed I pressed it, before cutting out the garment piece. Remember to flip the pattern piece over to get a left and right!
I widened the centre front panel so the bands would overlap rather than being edge to edge. I interfaced the front section of the neckband so it would support buttonholes and buttons.
I also added patch pockets with a flap and button.