These decals where made to work with the Monique 6 Skin. The body and limb decals will work on other skin types but the face decals won't line up correctly, so make sure you're using the Monique 6 Skin if you want to use the face decal too.
Simply apply the Decal and Normal maps in the Skin Textures tab
Credit to SupaRioAmateur for the Geoshell Oily Skin used in the first screenshot
