Preparing denim jeans for rugs is labor intensive. They are plentiful at the resale shops and from friends, so I don't make any effort to open seams, remove pockets, or take out hems. I trim around all those areas and then make one fairly straight edge on one side.
Here is a bundle that is probably enough to stuff 2-3 tubes for the shuttles.
I clip my threads when I'm done sewing and pull them out from under the presser foot. They will curl into a spiral and that needs to be straightened out before running the strip through the stuffing machine.
I am using a twill tape to keep track of the rug length and the temple that came with the loom to help keep a consistent width to the rug.