Now for the record, I stole this piece of foamboard from work so it already came silver. I usually paint the foamboard myself. Mind you, the stuff DOES warp and the way to create a FLAT wall is to make cracks on the BACKSIDE of the wall (since no one but you will see it).
Painting time! You can use whatever you want. I tend to use GamesWorkshop paints. Fairly cheap, come in a million colors, etc. IF I were doing the wall, I'd go to Lowes and find a paint that I'd like. Might cost a few dollars to get a small can, but I have had them make me custom paint. So the wall is silver, the doors are TIN BITZ and the piece on the bottom is BOLTGUN METAL.
This is just how I'm doing things, but I am trying to add more texture to the walls. I'm not a fan of copying wallpaper from the FILES section and taping it on. If there's brick, I actually want there to be texture! That explains the molding piece on the bottom of the wall. It just adds a tiny bit of dimension.
I've glued the pieces on. Is it done? Nope, not by my standards. I'll frame the double doors with the same BASSWOOD sticks that I did on the bottom. This can get costly and it's hard to remember what size you bought cuz, uh, there's a lot to choose from. The doors are BASSWOOD also, available at any art or hobby store.
(I ran to the store again after class to pick up more studs and a few more flat pieces. 4 of those studs and the flat pieces cost a bit over $6 in the end. What sizes you choose is up to you.)
That's about it for this phase. I have ideas of what I'll add next but since I don't diagram my stuff out, I just kinda do it on the fly. This is a simply project and this piece will be used as a generic door/wall combo. When I get off my lazy butt, I'll be showing just HOW you stand the wall up!