That was a joke, lol. And it was pretty funny Paul. Now back to you kisenok
Sry for the diversion. Felt good to laugh.
OK. First of all, you know that the mud in this photograph is not photoshopped onto the girl. That is real mud really applied. That is not to say you can't simulate it and decrease your hand painting and/or cloning somewhat. Secondly, it for this exercise, it helps a lot to have a good mud texture. I couldn't find one I really liked but I can't say I looked very hard.
I'm no expert at this kind of thing, but here is what I did.
I made a separate layer of the right half of her face and extracted the BG for the clipping mask. In the layers panel, this is layer 2 and I used a mask for part of the extraction.
One of the reasons I say this isn't good mud is that you want a smoother texture. Then I made a displacement mask. (this is another tutorial but the steps are easy if you need them) The purpose of this map is to bend the flat surface of the mud around the contours of the face. For this image I used 10 horizontal and 5 vertical. Those numbers might work with a lot of other portraits too.
Next step is to clip the mud texture to the half face. Now go to filter>distort>displace and add the displacement map effect. The result I have is very subtle and that's often the case. But I will help that along later. Next add a layer mask and paint away the places where you don't want the mud on the face, hair, etc. (apparently I erased some of the texture itself - don't remember doing that, sigh, and I don't recommend using erase when a mask is non-destructive)
I set this layer to multiply but another mud texture might be fine on normal or another blend mode.
As I said, I wasn't entirely satisfied with the displacement map result, so I made a copy of the half face, placed it above the mud texture, changed the blend mode to overlay and decreased the layer opacity to 80%. This adds shiny highlites and brightens up the whole face (half face), slightly emphasizing the contours.
Finally I made another layer, got a soft 100% white brush and added more highlites and set this layer to overlay, opacity of 40%.
Well, there you have it. My idea for the day, lol. Hope this helps.