Set up your gear in front of a window. Using the window frame as the borders of your study, move around until the scene out the window makes a dark/light pattern that appeals to you. You may end up working from a standing position, or you may have to sit on the floor. Form trumps function for this project.
Make a quick sketch, in monochrome. This can be a postcard-sized pencil sketch, or a purple watercolor. The important thing is to map out the shapes. It is not necessary to take responsibility for the viewer being able to identify what they're looking at. Just show them the shapes.
Now, where would you like to go with this pattern? A warm/cool arrangement? A soft-edged interpretation, a la Whistler? A geometricized abstraction? Hold on to the dark/light array of shapes, and let go of everything else.