I make virtually all interiors by constructing a 3D model in Sketchup. I find it extremely useful, since I can change perspective and move around stuff as I want. Tip: Use 2 point perspective camera when capturing the scene, so you don’t get the skewed 3d-esque angles everywhere (seen below).
This kind of perspective would work better in a hi-res game, but in 320 x you want all lines to be as straight as possible.
I usually just use the screenshot button to capture the 2d view, and all the lines will be perfect, non-antialiased, single pixel width, suitable for quickly filling areas with paint, etc.
After importing the picture in PS, I resize it, and spend lots of time fixing the scaling artifacts (going down to 320x resolution will create plenty of blurriness).
I usually reduce brightness and saturation a lot, since that gives me better control of the lighting. I then decide where the light sources are, and I start increasing saturation where the light hits objects and surfaces.
A pub interior is usually rather dimly lit, with spots of light here and there.
There’s a basic bluish hue thanks to the window, and the light sources inside will have a nice complimentary orange-ish hue. This is an extremely common way to light scenes (often over-used, imo, probably due to early MI backgrounds, where the only colours are superblue and bright yellow).
This is not your typical cozy irish pub with wooden panels and antique decorations, but a cheap, plastic, fake-marble Swedish pub/pizza place. The jukebox is traced over a photo that I’ve skewed to get the proper perspective. The pillar made me a bit uncertain – since this is a top-down scene, there’s no ceiling to connect the pillar to, so it’s just left with a black top. I hope it still looks like a pillar, and not some giant trash can.
Enlarged, so a bit blurry. I still consider it a wip, as there’s some more refining to do.