It is simple. Wax painting uses colored wax as the medium instead of oil paint or acrylic or watercolor. No brushes, just a heat source and sometimes a wind source to move the hot wax around the board or canvass.
Of course there is much more to it. The artist must choose her wax. My wax of choice is a mineral source non-toxic wax. The acid free wax is infused with powder pigments in a wide variety of colors. As I said in the sidebar, I do not do encaustic wax painting with bees wax.
After my painting is finished, I cover it with a hard clear coat for protection.