Metamorph Salamander

I am trying to figure out the best time to put this guy into his box of pine bark mulch (moisturized of course ) How long does he have? Or is he ready now? I have no clue, totally new at this, trying hard to gather as much info as I can. I had sent pictures to a guy and he replied with "
What you have captured is the larvae of a salamander in the genus Ambystoma. It is most likely a Spotted Salamander (A. maculatum) or Small-mouthed Salamander (A. texanum), but could also be a Unisexual Ambystoma. These little guys swim the waters of wetlands feeding on little invertebrates (like mosquito larvae) from the time they hatch (April) until around early July, when they go through metamorphosis and transform into land-dwelling salamanders.

So if that helps at all. I want to give him the best home possible. help what do I do ?
Also I did notice this morning that it seems he is "shedding" thin little layers appear to be falling off his body and tail.

He still has his gills so he isn't ready to leave the water yet. Make a little land area for it and it will let you know when it wants to leave the water by climbing up on it.

There's an embankment there and some bark waiting for him. Thank you Gills are nothing but tiny nubs now!!

It happens so fast You may find that it'll hop in and out of the water for a little while after the gills recede. If you can can you add some more photo's ?

I just cant get over how adorable that face is! He (I say he but obviously I have no clue if its male or female) is about 7.5 cm long from nose to tail. He takes gulps of air a lot, and spends a good amount of time hiding under his bark bridge, but he comes out to say hi when I come home and does eat, however he doesn't each much, I have gathered that when they metamorph they usually won't eat much.

Still not getting out of the water, but he eats! So I figure that's a good sign. Any idea what type of salamander this is? I found him in mid Michigan in my dad's pond in the woods if that helps.