I've never done this before and i screwed up the roof. but I kinda have the idea. and the lower color was supposed to be grey or silver but the marker lied about it's color.

Good start!

What markers are you using? If you're going for accuracy, buy a set of Cool Gray Prismacolor or Chartpak Ad markers, they're more expensive but the results are lightyears better. They are numbered to tell you how dark they are. For example: Cool Gray 1=10% (the lightest gray), 2 is 20% and so on up to Cool Gray 9=90% (almost black). Start out with the lightest and work your way up. You can also get sub-shades by going over an area once, let it dry and go over it again with the same marker. It will get darker each time. You can usually get 3 shades from one marker.

Use a colored pencil to do the pinstripe.

Good Luck!

Ben

what is the price range on those markers?

I haven't bought them in a while but I think it's $35 for a set of Prismacolor Cool Grays (10 pack), you can probably buy them individually too, and it's around $3 each for the Chartpaks. Very expensive, especially for a one time thing. Check local art supply stores. They have the best selections and sometimes allow you to try them out on scrap paper before you buy.