Turn off the water supply that leads to the galvanized piping. This is usually done by turning off the tap under the sink. If necessary, turn off the main water supply from the valve located in your basement or garage near the water heater.
Clean and dry the pipe's surface. Remove all excess dirt and water. If the pipes aren't dirty, just wipe them dry to remove any surface dirt and the water from the leak. If they are greasy, use a cleaner that cuts grease, such as dish soap, to clean them.
Measure the pipe's diameter using a diameter tape. Wrap the tape snugly around the pipe near the leak to get the measurement. Use a pipe clamp that fits the diameter.
Position the pipe clamp so the rubber section fits snugly over the leak. Tighten the clamp as tightly as possible to prevent further leaks.