Step 1: Materials
something to cut
eletric tape(not in image)
Step 2: Prepare the Wires
Step 3: The Tips
Twist the 2 of the same color(in my case they were cooper colored) because those are the ground wires.
Step 4: Connector
Step 5: Solder
Pay attention to the wires order. The tip is for the right side audio, the inner ring is for the left side audio and the "base" is the ground. You can test which wire goes were with a multimeter or batteries and LEDs.
Put them in the right place and solder.
Do it in a well ventillated place to avoid health injuries.
Step 6: Protecting
This connector needs this black part which I put over the connections.
(I got the photos wrong XD)
Step 7: Fitting It All
The black back part then can be screwed to the metalic part.
Depending on how you soldered and taped everything, some pressure may need to be applied.
Step 8: Finished
ANY DAMAGE CAUSED BY THIS IS THE READER'S RESPONSABILITY.
That was just for precaution.
Unfortunately, I couldn't test it yet. But it seems to be working according to my multimeter.
Thanks for reading it all. This is my first instructable. Sorry for English mistakes. Leave good critics in the comments.