Using the Greenlee 746 hydraulic knock - out ram is easy. First, make sure the ram is placed on a stable surface. Connect it to the appropriate hydraulic power source according to the instructions. Once connected, you can start the operation. When using it, keep an eye on the pressure to avoid overloading. For maintenance, after each use, clean the ram with a dry cloth to remove any dirt or debris. Store it in a dry place to prevent rust. Check the hydraulic fluid regularly and replace it as needed. Also, inspect the ram for any signs of wear or damage, and if you find any issues, have it repaired by a professional.