Foundation helps boost every other makeup products (that goes on the face!) especially powder by creating a smooth surface to glide on for a smooth finish.
However it's important to get the foundation and its application right to achieve a flawless look. Note that before applying the foundation, you should exfoliate, cleanse, prep/prime the face before finally applying the foundation and more products.
There are different ways to apply foundation but it's best to master a modern, long lasting method for a flawless application.
Watch and learn in easy steps above.