This is a really interesting one. I remember doing dirtying down at college and hating it. I didn't like the product we were using as I felt it just ruined the look. However this was a really fun way of dirtying down.
For explanation purposes this will be explained for application on the arm.
Put some Fullers Earth into a bowl and mix with water until it is at a thick consistency.
Using a palette knife smooth onto the skin. You can apply it with brushes to get a different texture. I normally use my hands to apply it. It gives a more uneven finish
When you're happy with the coverage, use the hair dryer on a warm heat setting to dry the Fullers Earth
As it's drying, you can see it beginning to crackle and pull apart and it's getting lighter. When it's dry you can spray coloured hairsprays on it. I did mine with browns and greys.
You can also use greaspaints ontop of the fullers earth. I actually prefer to 'dirty' the skin with them before applying the fullers earth that why when it cracks you can see the colours underneath.
You can use fuller's earth dry on the skin, and dust it over the face. Good for post-apocalyptic shoots.
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