Using the ProsKit DP-366D Desoldering Pump is easy. First, heat the solder on the PCB with a soldering iron until it melts. Then, quickly press the button on the desoldering pump to activate the suction and remove the molten solder. Make sure to keep the pump upright during operation for better suction. When it comes to maintenance, clean the pump regularly to remove any solder residue. You can use a small brush to clean the tip. Store the pump in a dry place to prevent rusting. Avoid dropping the pump as it may damage the internal components. Also, don't use excessive force when pressing the button as it could break the spring.