Lenovo YOGA BOOK YB1-X90F Safety, Warranty & Quick Start Manual page 6

Starting to use your tablet
You might need to charge the battery before using your tablet.
Charge the battery as shown.
The best way to charge your device is to connect your tablet to a power outlet using the
included cable and USB power adapter.
Low battery
Turning on/off
Fully charged
Turn on: Press and hold the On/Off button until the Lenovo
logo appears.
Turn off: Press and hold the On/Off button for a few seconds,
then tap Power off.
Restart: Press and hold the On/Off button for about 10 seconds
until the device turns off. Then turn it on again in the normal way.
4
Charging