Hold down the screen key, the light will display the time, and press again to display the date.
After adjusting for hours, press the screen key and do not let go. The same method is used to adjust the minutes.
Long press does not let go, after a few seconds, the hour is beating, press a screen key to add 1 hours.
Then the same steps and methods are used to adjust the month and day.
After adjusting for a minute, then press long, and adjust the year after a few seconds.