Press and hold the Top button and either Volume button until the power off slider appears
Drag the power off slider to the right
Wait for the iPad to turn off completely
If the screen is frozen, quickly press and release Volume Up
Quickly press and release Volume Down
Press and hold the Top button until the Apple logo appears, then release
If needed, use Settings
Open Settings
Tap General
Tap Shut Down
Drag the power off slider to the right