From the picture, it looks like you went for silver colored nylon either in size 1/4" or 3/16.
It looks a little too big.
I think 1/8" would of been good.
or 3/16" if you used 1/4".
Your heatshrink at the headphone end side should be a little thicker.
At least two layers, so that they don't spring open.
Hope you also used adhesive lined heat-shrink or some hot glue on the sleeving before putting it over.
Besides that, the cable looks good.
I like wood.
Kind of matches the color of the headphones.