Plant and water them. A rhizome is a modified stem , much like a bulb . Get them in some moist soil and wait a few days to weeks and you should see some growth.
It seems the general rule is about 4" deep in a 1' mound 3-5 feet apart . I would place a tablespoon of balanced Osmocote ( 10-10-10 , 15-15-15 ...) about an inch below the rhizome . Keep moist, not wet till you see growth. Hops are a weed and a cousin of cannabis they will take off and grow almost anywhere . Have fun , relax and get a book about growing hops. If you find things that help or hurt them post your experience so we all can learn with you :-)