1) The opening scene shows Dexter smiling as he kills a mosquito, revealing his enjoyment of killing and sinister nature.
2) Scenes of Dexter's morning routine, like shaving and eating, are filmed using close-ups and music to imply that he enjoys drawing out death and finds pleasure in murder.
3) Mundane daily tasks like getting dressed are shot and edited to depict murder, showing that Dexter sees killing in all aspects of life and anyone could be a murderer beneath the surface.