Comment on Heatherzart's profile

If you haven't already - watch the video on my profile page.  It's fast but it shows how many times I go over the same area.  Scratch LIGHT - don't try to get your white whites right away, build up to them.  The harder you scratch, the more permanent it will be - keep your instrument sharp (I toss blades every could of hours for a fresh tip) and lightly skim the surface.
Your pencil background will help you just remember that there's no coloring in spaces, your whole picture has to be filled with lines so map out your lines ahead of time so there's no confusion.  patience….. go slow and use a GOOD board - Ampersand or Essdee - all of the cardboard stuff is crap and you won't be able to layer with it.

Good luck!  Send me pics