1. To make a bag: you can cut the jeans, (or even just use back pockets by undoing stitches) and sew the pockets together. This will create a little pouch. When you sew them together, leave a little room and you can insert a ribbon, etc. to make a handle of whatever length. When you use actual pieces of jean cloth, you can fray the ends before sewing for a neat effect. To add a flap, make one piece one-and-a-half times as long as the other, so that it can fold over. Then you can sew or glue on a button to fasten into a hole you make in the larger flap. These can be decorated with buttons, sequins, beads, etc.
2. Binder cover: Adding seam allowances, open a binder flat on your fabric and trace the entire binder. Then make two inner flaps. These will form a pocket in which to insert the binder cover. Make the pattern for these flaps by tracing the front cover only to the bend at the spine (add seam allowance all around). Flip this pattern for the back flap. Hem the inside vertical edge of the two inner flaps (the edge that will be nearest the spine) then (right sides together) sew each to the outer section at the top, bottom and outer edges. The edges nearest the ring mechanism is left open. There will be an unfinshed edge at the top and bottom of the spine. Simply make a topstitched hem. If you are going to add details like pockets, patches, embroidery, etc, do that before sewing the inner covers to the outer cover. Contrasting piping would be a nice detail that can be added as you sew the inner and out covers together. To insert the binder, bend the binder covers completely backward and insert them into the front and back "pockets". They will fit snugly like a wellmade slip cover. This method is much easier than using a zipper, requiring only straight sewing and no zippers.
3. Make bows: just fold and sew the edges in (or leave them frayed). Cinch the middle and wrap around another small piece of denim, then glue or sew in place. You can attach these to hair clips, use them on gifts, decorate clothing, and more!