Again just the standard of sketch, flats, shading and lighting! I got this bomb ass set of cityscape brushes for CSP and had to use them here though. Specifically for the bricks. I really love how they had a brush for varied bricks, it was pretty much perfect. Also did my usual of fucking around with my lighting and shading. This time a LOT of multiply layers and hard light layers. Hard light is pretty good for variation with light and make the background pop a bit more. Also makes the shading feel a lot more natural and sets the tone well!!
Hope this helps a bit! If you have any questions feel free to ask in comments or even request a tutorial :D!