Reducing humidity in your home is one method to prevent an infestation of silverfish, and this can be achieved through a dehumidifier or improving ventilation in some climates. Proper food storage cuts off their access to certain foods, too. While they can still feed on a plethora of things, this limits food sources. For a natural repellent, cinnamon is known to keep silverfish away. Finally, filling in cracks and crevices will prevent them from entering the home in the first place and limit the options for where the female can lay eggs.