You’re the cinematographer and your assignment is to light a scene. You need actors, props and a location. What mood do you want? The scene’s mood will be influenced by how you decide to light it, the environment you use (e.g. a dark basement or a spring meadow at dawn), the nature of the subject (e.g. are you shooting a sweet baby or an evil doer)
Don’t just rely on available light, light it. Use setup lighting to enhance the mood. Do you want dark and moody with lots of shadows and mystery, or do you want a light and airy feel? How can you use light to help communicate the mood you’re after? Think about how you would motivate the light, how will you place the light in relation to your subject? Think about the color of the light sources and how they may benefit the image or distract from your intended purpose. For example if you are shooting a bride or baby, do you want your background to have the green of fluorescent light?