this is the original image

in this step used, clone stamp tool and started to remove the hair. and also used healing brush tool.

the same was made with the nose and the eyebrows. using clone tool and healing brush.

the first is to create an adjustment layer. when you open the circle with half white and half black. creates this layer. click on levels and there press the white bottom right arrow and move it toward center. the midtones ( gray upper center arrow) move it to the right. press ok and draw a line in the center of the face. right click and open blend options. open emboss and contour. inner bevel, smooth, depth 60% size 13 soften 3. angle 30 and 30 highlight screen shadow multiply. press ok

now the process is repetitiv. open new layer adjstment, click on levels and move the white bottom arrow to the center and the upper gray arrow to the right. depending how dark you want the color. NEXT press rgb in the same level adj. and if you want the color more greener. take the white bottom arrow of the blue and red and move it to the center until you get the color you want. then press ok. that creates a mask. press ctrl + i to invert, and choos a brush and give it the size you want. pick the white color and start painting. this is the same metod you have to use to paint with different colors. and the size of the brush its up to you.

you have to be patient. and try over and over until you get what you are looking for. remember. adjst layer-levels-white bottom arrow to center. press rgb to change the color you want. press ok. go to layer mask and press ctrl + i.

this is what you are getting. added a red color in the eyes and used liquify to make the thumbs bigger.