Speed: To use the oral irrigator, first fill the 350ml water tank. Then, select one of the four cleaning modes (gentle, normal, DIY, or powerful) using the control buttons. Place the selected nozzle tip into the water tank and position the tip in your mouth. Turn on the device and use the tip to clean your teeth and gums. After use, remove the tip and clean it, then store the device properly. For detailed instructions on adjusting water pressure, cleaning the unit, and precautions, please refer to the user manual.