The answer to 'how to prevent silverfish' is to eliminate their food sources, moisture, and entry points into your home. Silverfish feed on starches, sugars, and proteins found in common household items like paper, clothing, and glue. Reducing these attractants and sealing cracks and crevices where they hide can effectively prevent silverfish infestations.
Start by thoroughly inspecting your home for signs of silverfish, like their shed exoskeletons or droppings. Then, focus on reducing moisture by fixing any leaks, using a dehumidifier, and improving ventilation. Remove their food sources by storing dry goods in airtight containers, regularly vacuuming and cleaning, and eliminating paper clutter. Seal any cracks, crevices, and entry points with caulk or weatherstripping to block their access. You can also use diatomaceous earth or boric acid around baseboards and other areas to kill silverfish.