Need help soldering two different 3.5mm TRS cables together

I’m trying to connect my DT 770 wire to the end of an old 3.5mm TRS AUX wire I had laying around, the DT wire has a left right and ground but the misc cable has two wires.

Is the copper coming out of both ends supposed to be the ground?

Which is the left and right of the misc wire?


That goes to “sleeve”