You can define the working hours of the printer in WebTools Express.
Enable [Automatic on] first, to let the printer wake up automatically. Define the working days with the [First working day] setting, for example 'Monday', and [Last working day] setting, for example 'Friday'. And set the wake up time and shut down time with the [Start-up time] and [End of working day time] settings, for example '06:30' and '19:00'.
That way the printer turns on and off automatically, at the set day and time.
Even if [Automatic on] is disabled, the [End of working day time] setting is active and causes the printer to automatically switch off at the selected time (due to power saving regulations, the printer must always shut down once in twenty-four hours).
If the printer was manually powered on outside the defined working hours, the printer will automatically switch off instead of going to sleep mode after the selected [Go into sleep mode after] period has elapsed.
The printer now wakes up automatically, and is active during the preferred time frame on the set days.