Here is the palette Beth listed based on Robert Liberace.
My Portrait Palette, based on Liberace’s
Cad Yellow Light * ** ***
Cad Red Light
Pyrralo Ruby * ***
Alizarin Crimson **
Cobalt Violet Light
Cobalt Violet Med
Cobalt Blue Turquoise Light ***
Cobalt Blue Turquoise
Phthalo Green **
Viridian Green Light
Flake White * **
First, I think we should find the Munsell notations. I know, for example, that Cad Yellow Light is likely 5Y 8.5/16.
Remember that flesh ranges from the 1st to the 5 or 6th chroma, from the grayishness of a shaved beard to the ruddiness of a baby's cheeks.
So, first of all, the mixtures must be neutralized in one way or another to fit within this range. How is it done?
A mixture of Pthalo Green, Alizarin Crimson and Burnt Sienna, plus white, should make a dead neutral, theoretically. Or, one can use Cobalt Blue, Aliz Crim and Burnt Sienna. These mixture will neutralize any mixture.