Press the ON/OFF button, then the KEY button to unlock the plates, select the plate you want to turn on, increase or lower the temperature with the + and - buttons (from 1 to 9).
To turn off use the ON/OFF button. The letter H will appear flashing to indicate that the straightener is still hot, it switches off automatically when the straightener cools down. if you want to set the key lock for child safety, press and hold the key button.
NB. don't set any timer, thanks