A rag rug is the perfect craft for all those harbouring a box of clothing so scrappy that even Goodwill wouldn't want to touch it. Rag rugs are also known as toothbrush rugs because those toothbrushes with holes in the handles -- when sharpened -- happen to be perfect tools to make them, although they can also be made with large handicraft needles.
Cut or tear your fabric into strips, 1/2-inch to 1-inch wide. If you like the raggedy look, leave them as is, but if you want a slightly neater-looking rug, double-fold the strips and baste them using a sewing machine.
Join two fabric strips together. Sew them, or join them together by cutting holes in one end of each strip. Thread the non-hole end of Strip 2 through the hole in Strip 1, then through the hole in the other end of Strip 2 to create a slipknot.
Cut a hole in the other end of Strip 1. Thread Strip 1 through the hole in your rug tool, and then thread the other end of the tool through the hole in the end of the strip to knot the strip to the tool.
Leading with the tool, thread Strip 1 over, then back under Strip 2 to create a loop. Bring Strip 1 up through the loop from underneath the work and pull the knot tight. Repeat four times.
For the fifth knot, instead of winding Strip 1 around Strip 2, bring the tool over Strip 2, down through the fourth knot and up between the two strips, through the loop that creates. Repeat, continuing through the four knots and around to the other side.
When you run out of unknotted strip, join two new strips to their ends using the same technique you used in Step 2. Continue knotting around and around until your rug is the desired size.
Half a pound -- or 2 yards -- of fabric for a square foot of rug is a good rule of thumb. A tool specifically intended for the manufacturing of rag rugs can be had from any craft store, but a large wooden needle, a sharpened old-fashioned toothbrush with a hole to hang it from in the handle or any pointy stick with a hole large enough to stuff a strip of fabric through will do. You can also make your own with a length of wire and some electrical tape. Cutting up old sweaters makes an absorbent rug ideal for the shower.