Prime the wooden column with a white primer. Let dry. Sand the column. Apply a base coat of the Black Licorice paint included in the Florentine Green Plaid Faux Finish Marbleizing Kit. Let the base coat dry.
Moisten the sponge that comes in the kit. Pinch and tear off the edges of the sponge to make an uneven edge, which will give a more random sponging pattern. Squeeze the two colors of green paint -- a light green and a dark green -- in a swirling motion onto a paper plate, one color on top of the other.
Squeeze a little of the white veining color on top of the green colors. Squeeze some of the thickener/extender atop the paint. This makes the colors begin mingling together. Turn the plate slightly in your hand to bring the paints together, but don't stir them. Dip the sponge into the paint mixture and press it onto the column. Use a sponge wedge to get into the smaller crevices. Let the paint dry.
To get an authentic marble look, add veining and cracking with white paint. Mix equal amounts of white paint and thickener/extender, dip a feather (included in the kit) into the paint mixture, and apply veins diagonally at random. It's best to work "nervously," without much control of the feather, to get a realistic look. Add as much or as little veining as desired. Remember, real marble varies.
To add a crack, use the feather and the white paint mixture to apply a line thinner than a vein in the opposite direction as the vein. When intersecting the vein, move the feather down slightly and continue the crack to replicate marble shifting when it cracks in real life. Let the veining dry.
Apply a coat of glossy acrylic spray finish for a high shine.