You can use a wide variety of products both underneath and on top of your skin camouflage.
Many products are often used beneath skin camouflage without causing a problem. If you are using an acne treatment, moisturiser, invisible primer and/or a sunscreen then you should apply it to your skin before you apply your skin camouflage.
You will need to allow a few minutes for your skin to absorb these products, and remove any excess residue as it can prevent the skin camouflage from staying in place.
Decorative makeup is commonly used on top of skin camouflage and both powder and liquid makeup products are fine to use. Skin camouflage is also frequently used as a foundation, although you can also use a makeup foundation on top of and underneath skin camouflage.
However, you should avoid using makeup products that are similar in colour to the skin discolouration that you have covered using your skin camouflage. Using a makeup that is similar in colour to the discolouration that you have covered can play a trick on your eye and make it seem like the skin discolouration is showing through your camouflage, even when it is not.
For example, if you use a pink-red blusher on your cheeks after you have covered reddish acne then it may appear as though the acne is still visible through the skin camouflage and makeup. This is because you are likely to be very familiar with your own face and your mind will make automatic assumptions as to what it perceives when it sees the pink-red colour.