Using this door interlock switch is easy. First, make sure your washing machine is unplugged to avoid any electrical hazards. Then, locate the old switch and carefully remove it. Match the mounting holes of this new switch (which are 43mm and 30mm apart) with the corresponding holes in your washing machine. Connect the wires to the 3 terminals as they were on the old switch. Once everything is connected, plug in your washing machine and test it. As for maintenance, keep the switch clean and dry. If you notice any signs of damage or if the switch stops working properly, it's best to replace it right away. Remember, safety comes first when dealing with electrical appliances.