For me, a huge part of creating a game is doing the scenery - building the image of the world, as it were. It's not only satisfying to create the look of your world, it's also important to focus on functionality of the scene too. Backgrounds that look great but are impractical are pointless, so there's a lot to think about in terms of what the player will need to interact with, whether exits are able to be found, walkable areas and the like.
For PISS, I really want to create an interesting, exotic world. I want it to be familiar and yet also quite alien - you should be able to recognize a building as a building and a tree as a tree, but it shouldn't look exactly like the buildings or trees that we see every day.
I'm thinking a lot about colour palettes, light sources and the form of things in order to achieve this. Instead of a blue sky, mine is green with yellowish clouds. Rather than choosing to have yellow lights as I usually do, I've gone with bright blue ones.
It's something I've really pushed - putting interesting things in each scene. I want you to look at the backgrounds. I want to build a world that you as a player want to explore and discover things about. For me, I love it when I see a scene from a game that captures my attention and makes me think "I want to go there". Make the visual elements of a scene - beyond composition, colour and functionality - interesting. Make lights, banners, statues, doors, plants and buildings that will make people interested.
A common thing when talking about decorating a house is the concept of a "conversation piece". For me, a game scene should have these. In PISS I want every scene to have at least one unusual element, one of these conversation pieces. Far beyond a stage on which to put your puzzles and story, a background is a piece of your world, and is so much more than a container for your characters and puzzles!