For shredded beef in a crock pot, I will cover the meat with water and run the crock pot overnight the night before serving. I will add some seasoning to the water, usually garlic, onion powder, and cinnamon.
Once the meat is fall-apart tender, I pour it into a strainer to get rid of the excess liquid. Then, after shredding the meat, I put it back in the crock pot with whatever sauce/seasoning I'm using.