To use an electric motor with a building hoist, first ensure the hoist is properly installed and secured. Connect the hoist to a power source and check that all safety features are operational. Turn on the motor and test the hoist's movement in both directions to confirm functionality. When lifting materials, ensure they are evenly distributed and securely attached to the hoist. Operate the motor to lift or lower the load, maintaining a steady speed and monitoring for any signs of strain or malfunction. Always follow the manufacturer's guidelines and safety precautions to prevent accidents.