I use Grindz and like and recommend the product. But you can also use minute rice or rolled oats. It must be parboiled rice as regular rice can damage the burrs.

Also disassembling and cleaning with a stiff brush works well. Really using a brush/vacuum is the best way then you don’t need to use coffee to clean your cleaner out. Never use compressed air cans, they often contain a bitterant to prevent abuse and the taste transfers to the coffee.