Replacing TRRS 3.5 jack wiring

There is no real standard for this kind of cable.
But here are some thing you could try:
- Pry or cut open the broken TRRS jack you're replacing, maybe you can follow the wire all the way to the jack.
- Use a multimeter to measure the four wires of your broken jack.

If you lost the bent/broken jack. You could also make a guess and test the headset before closing up, chances of breaking something when testing are rather slim.
If I had to guess I would say the following:

Tip : Left out
Ring : Right out
Ring : Ground
Sleeve : Microphone in

https://en.wikipedia.org/wiki/Phone_conn...)

The wires you describe:
white: Left out
Blue: Right out
One of the exposed copper wire will probably have an extra insulated wire inside, the other will not. Twist the exposed wire together as Ground and use the wire that is sleeved inside exposed wire as mic. Your essentially connecting the ground of the mic to the ground of the Left and right channels.

If you have extra TRRS jacks, you can always start over when testing and cut off a faulty soldered jack, since most jack you buy online will break apart due to the plastic melting if you solder and desolder the wires a lot.