You mustn´t forget that the films were shot on 70mm material, in a time when analogue was the standard. So a lot of the details get lost on film, making surfaces look like something else really easy. I.e. I am pretty sure that they did not go to the lengths and prime every panel several times and then sand everything down to get a perfectly smooth surface.
So it was (and still is) common to use wood as a basis and the paint it.
What usually helps a lot is a coat of wallpaper primer, giving the surface a sheen, depending on how much you thinned the primer.
As a basis to work on you can also use a decorative wallpaper that has no structure. You can then put everything on it that you want, i.e. plaster to make it look like a Tatooine sand structure.
But since you are going to use it indoors for private purposes I guess, you want a perfect surface. There is no other way than either using chipboard or plywood that has been laminated, or use plywood and do as exoray suggested.
To get a metallic look, you will of course need a metal colour and then probably several layers of clear coat or, again, that wallpaper priming stuff. The wallpaper primer is usually intended to make wallpaper watersafe, like in a bathroom, but it gives paint on wallpapers a very nice sheen that I usually have used on set to make dull looking walls appear more lively ;-)
I suggest that you make a few experiments on smaller pieces of board, to get a feel for working with the different materials and how to achieve what look.
Michael
if you have the book look on page 28
