Press the power button to turn on. To adjust heat setting, use the + or ¿ button. The curling iron has reached your selected temperature when the numbers on the LED or digital display begin to flash. To maintain a desired heat while using, press and hold the temperature lock button. A padlock symbol will appear in the LED screen when this option is in use. To release the temperature lock, press and hold the button until padlock symbol disappears from the LED screen. Once you have finished curling, press the power button to turn off and unplug the tool. This iron is intended for professional and consumer use. This iron has a polarized plug (one blade is wider than the other). As a safety feature, this plug will fit into a polarized outlet only one way. Do no attempt to defeat this safety feature.