The main purpose of putting makeup on the dead is to make them look as life-like as possible for the viewing.
This isn’t always easy, as blood pools after death, sometimes from broken or clogged blood vessels, sometimes because the body has been left in one position for a while.
The embalming procedure helps: since the fluid is colored pink, the skin takes on a “warm” look.
To finish the effect, there is a special kind of makeup especially for use by morticians, but many funeral parlors use regular commercial products.