To apply each of the textures, I selected the tab "Paint Tools", and then clicked on "Projection" (Fig.14).


In the bottom right of the interface, I selected the "Stencil” tab and then "Add Stencil” (Fig.15 & Fig.16).



Once chosen, the texture appears in the centre of the screen (Fig.17).



I used the shortcuts shown in Fig.18 to move, rotate and scale the textures.


Once I had the geometry and the stencil where I liked, I just clicked to start painting. This caused a pop up window to appear, asking for the resolution of the texture (I chose 4K again). After defining this and clicking on the "OK" button, it was time to start painting (Fig.19).


And … paint (Fig.20)!


To keep a good level of control while I paint, and avoid being destructive, I find that it's always good to work with layers. So I created a new layer by clicking on the "New Layer" button (top-right of the interface). After the already known pop up about the resolution appeared, I started working on the new layer (Fig.21).


For this new layer I chose a new stencil (Fig.22 & Fig.23).



And... that's all! I only had to export the textures into Photoshop to finish the work. For that, I right-clicked on the layers to get the exporting options.

After Photoshop the final texture looked like this (Fig.24).


The shoes area was left like that (with no texture) because for this I only used a procedural shader with the normal map. The lips were painted with a different shader and a mask was applied to control them.   

And here's the final image (Fig.25)!


I hope this small tutorial has shown you a bit of the creation process behind this image. Thanks for reading!