Modern washing machines work by spinning your clothes in a tub with water and detergent, and rinsing them by a spinning action. The dirty water then is pumped out of a drain hose and into your home's sewer system. Sometimes these drain hoses can leak. In that case, you need to replace your washer drain hose as soon as possible so you don't wind up with a laundry room full of water.
Unplug the washer or turn off the power to the electrical circuit where the dishwasher is installed.
Move the washer so you can gain access to the back of the machine. Use caution when moving the machine, as it will still be connected to the water supply hoses and drain hose. Have a friend or assistant help you if the machine is heavy.
Remove the drain hose from the sewer inlet. In the majority of cases, the drain hose will be hooked into the inlet by the goose neck on the end. It might also be secured with a clip. Loosen the clip before removing the end of the hose. How you loosen this clip depends on your installation. It could be a hose clamp, in which case you'll need a screwdriver or a wrench, or it could be a hand tightened butterfly nut, which pliers will help in loosening.
Remove the other end of the drain hose from the washer. How this is done depends on the washer model. It could either be a coupling type, which you unscrew before removing the hose, or a twist and lock model, in which the hose needs to be rotated in one direction (usually counterclockwise) before pulling out of the machine.
Insert the end of the new drain hose into the machine and secure by the method in which the hose was attached (See Step 4).
Insert the other end of the drain hose into the sewer inlet. Secure with a clip or piece of wire.
You can also use a plastic cable tie to secure the end of the drain hose in the sewer inlet.
Take the old hose to your nearest plumbing or hardware store so you can match it up when getting a replacement.