I have a card in the IFB gallery using this technique. 1st I colored with the metallic pencils on glossy--lots of pressure, lots of color. Brayered over with night of navy--again, lots of pressure with the brayer, you want dark color. Then rub the entire piece of cs with paper towel. This will take the ink of the metallic pencils and will make your glossy nice and shiny. Then if you need to "touch" up the flower with a little more metallic pencils.
Here's the link to my card if you want to see an example:
Gallery at Splitcoaststampers
Michelle