01. crop your image (in this case I flipped it but thats, obviously, optional) so you have your base:
02. duplicate your layer and go to image>adjustments>hue/saturation (ctrl+u), select the colorize button and play around with the setting until you get a medium bluish color. set the opacity to about 56% and erase all the face and skin areas. Now we have something like this:
03. create a new layer and fill it with a dark blue this is #050228 and set to exclusion 100% for something like this:
04. now I think this is a little dark so go back to your original, first layer of kate duplicate it and pull it to the top. Set to screen. Bring down the opacity to a nice level where it isnt too bright. For this icon it is set at 91%. Now we have this:
05. use this gradient (maker unknown to me) and set to soft light 100% for this:
06. create a new layer and fill it with a light, vibrant blue this is #C9DBEB and set it to colorburn 100% giving us this:
07. I'm pretty happy with the coloring so now we'll add some decorations. Go back to your original image or screen cap size it down to a fairly small size, crop her face, and desaturate it. drag it to your icon in progress and put it anywhere you like. We now have something like this:
08. Returning again to our original image or screencap size it down again (a touch larger than your b&w image) crop her face again and drag it above the black and white crop like this:
09. I'm not happy with the way the coloring looks of the cropped colored face so duplicate that layer repeat step 02 on it (go to image>adjustments>hue/saturation (ctrl+u), select the colorize button and play around with the setting until you get a medium bluish color set to 100% this time). where we are:
10. I want to add an exclusion layer but just on the colored kate face crop so while holding the Ctrl button on your keyboard click your last kate face layer (so it will just select the outline of this layer) create a new layer fill it with #050228 and set to exclusion 100% for this:
11. Too dark so duplicate the original kate face crop layer pull it to the top and set to screen at around 86% for this:
12. One last coloring layer while your colored face is still selected create a new layer add #C9DBEB and set it to colorburn 100%.
13. Use this texture place it around your cropped faces and set it to screen for this:
14. Final step: use a brush from the jammed together set by haydens__hunnie in white for the complete look
I have to thank neversince @ coffeefueled because her coloring tutorial really helped me out with this icon and the coloring technique I used on this was mainly from her (i.e. "#C9DBEB and set it to colorburn")
feel free to ask any questions.