The given answer suggests that if it was the person's last day on Earth, they would spend it preparing for the afterlife by training for what they will become. They also mention getting registered for a school to become a vampire, werewolf, zombie, or a mentally psychopathic individual. Additionally, they mention the possibility of being picked up by aliens. The answer concludes by expressing sadness and crying because the person believes they will never return to the face of light, indicating a sense of finality and resignation towards their impending death.