Purchase cranberries from your local grocery store. If you choose to, you can harvest your own wild berries. Wild ones can be found in swamps or you can grow your own in your backyard.
Sort through your cranberries and look for ones that are fully ripe, free of any damage and firm. Place them in a bowl.
Heat a pan of water until it boils. Add the cranberries to the boiling water. Allow the berries to sit until the skins split, but not until the berries turn soft and mushy. If they get to that point, they are no longer useful for dehydration.
Place berries onto a baking sheet. Place the baking sheet into your freezer for about 2 hours. (You don't have to do this step, but it will cut down your dehydration time.)
Place berries into dehydrator. You'll want to dehydrate them from anywhere between 12 to 24 hours. Make sure to rotate the trays and stir around the berries during the dehydration process.
Place dehydrated cranberries into a Mason jar or into a vacuum sealed bag for later use.