I take recycling very serious (almost too serious my family sometimes says) but when I had these shirts that I couldn’t use as rags, the plan to re-use took shape. Honestly, I remember my mom doing the same thing with old t-shirts.
The first step is to make sure the shirts are clean. Next comes the cutting into “yarn” by cutting around the shirt. Because t-shirts are knit in the round they make perfect continuous yarn without seams. Since the hem is double fabric, I make this strip thin but when I come back to angle the cut to continue cutting, I make the strips wider.
Joining the strips from each shirt together is accomplished with a simple square knot and the crochet continues. I use a Q size hook and single crochet stitch working only in the back loop of each previous row’s stitch. This produces a very sturdy and thick rug depending on how wide your yarn strip. Then when it is the size you want just fasten off and tuck in the ends. So gather your old shirts and give it a try.