Step 1
Disconnect your dishwasher from its power source. Unplug the appliance from the electrical outlet. Switch the circuit breaker switch that corresponds to your dishwasher to the "Off" position for added safety.
Step 2
Remove the dishwasher's bottom toe panel. Note that some dishwasher models require you to remove two to four screws to free the panel, while others have panels that may be removed by inserting a putty knife into the space between the front and toe panels and applying pressure to the metal clips that hold the panel in place. Set the toe panel aside.
Step 3
Locate the drain hose underneath the toe panel. Look for a 1 1/2-inch-thick rubber hose that runs from the dishwasher pump to a pipe underneath your sink. Use a pair of pliers to pinch the metal clamp that holds the hose in place to free it from the pipe.
Step 4
Pull the dishwasher 3 to 4 feet away from the wall so that you can access the floor underneath it. Check to ensure that the floor underneath your dishwasher is level; dishwasher drain pans are not as effective when installed over floors that are warped or uneven. Place a level on the floor and examine the horizontal tube; a bubble that sits between the tube's two center markings indicates a flat surface.
Step 5
Check to ensure that the drip pan fits properly. Position the drip pan so that the raised edges are against the rear wall and the sides of the cabinets.
Step 6
Reposition the dishwasher on top of the drip pan. Fit the drain hose to the pipe underneath the sink and secure it with the metal clamp.
Step 7
Apply a 1/4-inch-thick line of clear silicone sealant to the front edge of the drip pan to seal it to the floor; this prevents leaks from seeping underneath the pan. Restore the electricity to your appliance. Wait for the sealant to dry before replacing the dishwasher's bottom toe panel.