Very often I use my fingers for makeup application and this particular movement of tapping. Tapping is a great way to apply the product because the heat of your hands warm up products and then the skin. Almost all the products melt in contact with skin, which allows them merging with skin and that improves the overall appearance. The absorption of the product is also greater while tapping. Another one, of many benefits of tapping the product on the skin, is stimulating blood circulation which makes the skin plump, healthy and fresh.
By tapping you will not pick up dry flakes that are found on the surface of the face, which will create a more uniform surface for applying liquid foundation.
The liquid foundation is blended in a very natural way when you apply it with patting motion. One of the best ways for blending concealer is tapping. If you use your ring finger while tapping, you will get perfect results. Ring finger puts the least pressure on the skin and therefore is used for blending concealer on the undereye area.
And do not forget - wash your hands thoroughly, as you usually do and you are ready to apply the product.