Step 1 · Shut Off the Water Supply

The first and most critical step is to shut off the water supply. Since we're assuming there is no dedicated shutoff for the shower, you'll need to locate the main water shutoff valve for your entire home. This is typically found in a basement, crawlspace, or utility closet where the water service line enters the house. Turn the valve handle clockwise until it is fully closed. To ensure the water is off and to relieve pressure, open the faucet in the shower and a faucet on a lower floor (like a basement sink) to drain the remaining water from the pipes. Keep them open until the water stops flowing.