Wash the t-shirts you intend to use to create the rug first. This will not only make them clean, but test for colorfastness. You do not want to use t-shirts with colors that bleed for the rug project.
Lay the t-shirt out flat with the bottom facing you. Use the scissors to cut off the hem at the bottom and discard it. Then, cut into the bottom of the t-shirt and make a strip approximately one inch wide. Continue cutting this strip all the way around the t-shirt at an angle as if you were making a spiral up the t-shirt. You want a continuous strip from hem up to the armpits of the t-shirt.
Pull the ends of the t-shirt fabric strip gently. The fabric will curl over on itself and create a type of soft cord. This is the t-shirt yarn that you will use to make your rag rug. Roll the t-shirt yarn into balls for easy storage and use.
Begin the t-shirt rug by tying three ends of t-shirt yarn together in an overhand knot. Braid these three strands together using the following method. Put the right-hand piece over the center piece, making it the new center piece. Then, put the left-hand piece over the new center piece. Repeat this process until you come to the end of a piece of t-shirt yarn.
Insert a new piece of t-shirt yarn by braiding it into the rug alongside the end of the older piece of t-shirt yarn. Do not knot the pieces together as this will make a lump in your rug. Continue making this braid until it is long enough to make a rug out of it.
Thread the large needle with the stout thread or cord you are going to use to make the t-shirt rug. Tie it on to the beginning of the braid securely. Fold the end of the t-shirt yarn braid over to make a tight oval or circle and make a few stitches in the underside to hold it together. This will be the center of your rug.
Continue turning the t-shirt yarn braid around the center fold to make more layers. For a circular rug, simply turn it around in a spiral. For an oval rug, fold the t-shirt yarn braid into a long shape before adding more layers. Stitch the new layer of braid to the old one every two to three inches. Keep the stitches on the same side of the rug.
Finish the end of the t-shirt yarn rug by folding the t-shirt yarn ends back on themselves and pressing it to the rug edge. Use a few well-placed stitches to secure the end so the rug does not unravel or look unsightly. Your rag rug made of t-shirts is now complete.