I am finally getting around to showing you the next step in my technique. I started an image here, and wanted to show my next step. I have sprayed my image down with clear matte finish spray paint (a minimum of 6 light coats) so that the graphite is sealed. ****THIS IS VERY IMPORTANT!!!*** Without it, your drawing will dissolve before your eyes.
Once sealed, I use Burnt Sienna oil paint, with touches of Ultramarine Blue and Aliziran Crimson, thinned with Turpenoid, and brushed on. You can brush it on evenly or be random and let the paint run, depending on what you like. I put the thinner in the bottom of a metal bowl, then blobs of paint along the rim. I then run the brush along the paint, then lightly dip into the thinner, then brush onto my image.
The great thing is, if you don't like the color, you can still wipe it off at this stage... no harm, no foul.
Once on, you have to let the Turpenoid evaporate some, until the sheen disappears. I sometimes use a hair dryer to speed the process along, which usually only takes an hour or so anyway. Be careful with the dryer, though... you definitely want to dry it just enough so that the sheen disappears, but not much more than that.
Next step soon.