Lock the cow. Use a nose twitch and a rope. Pull the cows head
forward such that the cow's head, neck and spinal column form a straight line. Insert the line's head into the oral cavity at the tooth free rim of the jaw. Shove the line down the esophagus into the rumen until the mark on the line meets the incisors. Then the line's head is located in the rumen.
Remove the funnel for cleaning. Connect the line to a water tap and rinse it. Lift the line's head up such that the water runs down along the outer probe.