top layer is the pure mask, being that it is just either black or white, it is not necessary to keep it visible at the end (but if I have it visible I can adjust the second layer). That said, how do you create your mask, I am guessing a mix of magic wand and tracing by hand? God some images have nice thick lines and I can just use the magic wand and be done.
The second layer has the gray scale mask that gives the image better shadows and highlights. Although sometimes if it ends up having too much highlights or just makes the image look a bit weird I will lower its opacity (which is why I have the first mask enables). I create this mask by taking a layer making it black and white and burning midtones/shadows until they look like what you see, then I copy it over into the layer mask.
All layers underneath are what I uses to get the color. Usually just 2 but it depends. The first one is usually just linear burn until it reaches that state (sometimes multiple too). The next one is usually the burn layer where I burn the mid tones which help give definition, next I use a little linear light (depending on the image), then (using the same brown color "medium warm brown") I use color brush setting at like 30 too tone it down and turn browner. Then through the magic of messing with the opacity I get the color I want.
Obviously the coloring part can be done any which way, but just for the sake of me not spending that much time on an image I just use that as my default.
I just sum it up to different styles. I took the mask you had and made it in the psd style I use as an example if that helps (I am utter shit at explaining things) Also here is the psd a.pomf.se/nqgbxd.psd
using my style.>>1712005
Some asked in a thread a year ago to explain it, I posted a video of my process that I used a year ago (microphone didn't record and turns out i used a shitty screen recorder anyway)