If you didn't designate a reorder point when you set up your inventory items, now's the time to do so. Edit your inventory items and enter how many of each item you want to keep in stock. Then use the reminders list to send yourself messages to reorder. Every time the level of an inventory item in stock drops below the reorder point, a reminder to reorder is added to your reminders list.
Create a Reminder to Replenish Inventory