Set the screen brightness to low. Note: From the home screen, tap Menu > Settings > Display > Backlighting > Drag the Screen Brightness slider to Level 1.
Set the screen timeout to a shorter duration. Note: From the home screen, tap Menu > Settings > Display > Backlighting > Screen Backlight.
Turn off Bluetooth when not in use. Note: From the home screen, tap Menu > Settings > Connectivity > Bluetooth > Settings > Activation.
If you are traveling and do not have access to mobile or Wi-Fi networks, switch to Flight mode. Note: From the home screen, tap Menu > Settings > Profiles > Flight Mode.