What you'll need: Thin (cheap) hoop earrings. I found these in a box at my house by you can get them from Walmart or Claire's. Scissors, and two colors of embroidery thread. Cost: Under $5!
Start by cutting two pieces of embroidery thread in your chosen colors that are the same length, and longer then you think you'll need. I chose two different shades of aqua- one lighter, one darker. Tie the two pieces of string together and push the point of the earring through the knot. Then, start knotting your "friendship bracelet" pattern over the hoop. You can either hold the hoop inbetween your legs which is easiest, or make a little jig to hold the hoop so your hands are free to knot.
Keep each thread on its same side the entire time (ie- light aqua on the left, dark on the right). Knot each thread one at a time...
Pull each know fairly tight and pushed up against the previous knot. Be sure to switch off colored strings knotting one at a time, an then switching to the next.
The finished hoops, close up
Wear and enjoy!