And then share what you learned with others. That's how I roll. I went to a fun craft gathering the other day and learned how to make necklaces out of jersey knit t-shirts. So simple, they are totally going into my repertoire.
Supplies: A t-shirt (old, new, whatever, as long as it's a knit that stretches), a scissors, some thread and a needle. (You can also had beads (larger ones) if you so choose. 
(Note: I happen to be using a shirt with no seams on the sides, you will most likely want to cut those off, use your best judgment.)
Step One: Trim off the bottom seams and then begin cutting 3/4 - 1 In. strips, lengthwise, across the shirt. You will more then likely be cutting up most of the shirt (at least to the armpits).
Step Two: Stretch out each strip, if your seams don't break, you're most likely going to want to cut them anyways, this is up to you though. Once I had all my strips stretching I cut them to the lengths I wanted and lined them up shortest to longest. Since I didn't have any seams, I could cut where ever.
And Ta Da! A fun new piece to wear. Color and options are limitless. This is a great way to recycle/reuse older shirts or ones you can't wear anymore for some reason. Feel free to experiment with how you hide your seams.
