From a pair of straight-cut jeans, cut off each lower leg then cut along each inside leg seam.
With right sides facing, pin the inside seams of each piece together and stitch each seam to make a tube.
Trim what was originally the top of the pieces square and stitch across several times to form the bag base.
Roll the other raw edge back on itself to make a cuffed bag top and hand-stitch in place.
Hand-stitch a pair of leather bag handles or 2 strips of leather at top.