To keep a tackle box dry, it is important to store it in a cool and dry place. If possible, use an airtight container or bag that can be sealed shut. Additionally, you should make sure the tackle box lid is closed tightly when not in use. It is also beneficial to add some silica gel packets inside the box to absorb moisture and help protect your gear from rusting or corroding. Finally, if you are fishing near water sources like rivers or lakes, make sure to rinse off any saltwater residue before storing your tackle box away for long periods of time.