Measure out 14 inch long strips of your three different duct tapes. Fold them in half horizontally ("hot dog style") and press out all the creases and bubbles.
Look for the threads that are woven into the duct tape. With your scissors, cut the strip into thinner strips, with your scissors in between the tape's threads. Repeat this for your other two colors of duct tape.
Once you have the three strips ready, tape the ends together to hold them steady. The color of take that you use here doesn't matter, since you'll cut it off at the end. Make sure your strips lay flat side by side, instead of on top of each other.
Tape the strips down to the counter or your work surface in order to hold the braid steady as you work.
Begin braiding the three strands together. If you imagine your strands are numbered 1, 2, and 3, imagine that you take strand 3 and pull it over strand 2...
Then pull strand 1 over strand 3.
Pull strand 2 over strand 1. Pull strand 3 over strand 2. Basically, you're taking the outside strand on the right, pulling it over the middle, then taking the outside strand on the left, and pulling it over the middle.
Tape the other end of the braid so that it doesn't unravel. Once again, the color of tape you use here doesn't matter, since you'll cut it off!
Wrap the braid around your wrist to size it.
Once you've determined how big you want your bracelet to be, trim the ends of your braid. Then take a small piece of duct tape (here, it does matter what color you use!) and join the two ends together.
With the ends firmly connected, slip your new bracelet on!