This is a simple wire bracelet that uses an audio plug/jack pair as the fastener. It can be a great gift for your electrical engineer friend, or a way to express your own enthusiasm for all things audio.
Step 1: What You'll Need
1. A pair of needle-nosed pliers
2. Two different colors of insulated wire (I used blue and white here)
3. A spool of 26-gauge (or similar gauge) un-insulated wire
4. A matching mini audio/phone jack and audio/phone plug. The "mini" sizes of both (typically 3.5 mm diameter) work well for this particular bracelet, but you can adjust the number of wires/bracelet thickness if you're using normal-sized plugs (typically 6.35 mm diameter). You can find parts here: for the plug and for the jack.
Step 2: Unscrew the Plug
The plug should be able to be unscrewed as shown. This is convenient for us; it lets us attach the wires for the bracelet nice and securely to the bracelet fastener.
Step 3: Attach the First Wire
Wrap the un-insulated wire a couple of tires around the inside tail of the plug; if you wrap tightly enough, you shouldn't need any other form of attachment (glue, solder, etc.).
Because this is an audio plug, there should be a hole on the bottom of the plug's outside shell. Through this hole, thread the un-insulated wire through the outside shell, and re-screw the plug together.
Step 4: Measure + Cut the Wires
Measure the circumference of the wrist of whoever will be wearing the bracelet, and add 8" - 10" to that measurement (better too long than too short!). Cut the un-insulated wire to this length, along with the two colored, insulated wires.
Step 5: Attach Insulated Wires
This part is a tad difficult and might require some trial and error. First, tuck the ends of the two colored wires into the plug's bottom hole; they should just barely fit.
Call on all the hand muscles and dexterity that you've got, and as tightly as you can, twist and wrap the un-insulated wire around the two colored wires in a figure-eight, as shown. Keep making figure-eights until you feel that the colored wires are secure. The key to this is to keep the un-insulated wire as taut as possible while you're wrapping.
When you've made enough figure-eights, carefully thread the un-insulated wire underneath the first figure-eight (you might have to shove it through with the pliers a bit), and between the two colored wires. This acts to secure the wrapping.
You can check if you've been successful by lightly tugging at the colored wires, one at a time, and seeing if they're loose. Realistically, "light tugging" is the only strain they should have to go through as components of a bracelet.
Step 6: Combine/weave the Wires Together
Take the three wires into hand, and pull them together into a single strand using your method of choice. Here, I've used a simple braid. Feel free to use a more complicated weaving method, thread in some beads, or customize otherwise at this step.
Step 7: Attach the Jack
When the braid has reached a desired length, it's time to attach the other fastener component--the jack. Get your hand muscles ready again, and end the braid by looping the un-insulated wire in figure-eights around the colored wires like you did earlier. Loop the un-insulated wire over the first figure-eight as shown, to secure the braid end.
Now for the trickiest part of the bracelet. Use the little metal tabs and the shape of the jack to secure the three wires to the jack. There isn't an exact method that I can give you--just tips:
1. Use the needle-nosed pliers to crimp the wires to conform to the exact shape you want them to be.
2. Aim to create a sort of tight "cage" that the jack can sit inside.
3. Leave enough end length for each of the wires to "tuck" them back into the braid.
4. If you can't seem to find a good method with just wrapping, you can also neatly coil the wire ends together and use an adhesive or a jewelry part (like a ribbon clamp) to attach the jack.
Step 8: Completed Bracelet!
There you go! It may take a few tries to get it right, but when it does, it looks awesome.