Follow the tips below to save battery before it gets switched off.
1. Turn off GPS/Location Access, Bluetooth, WiFi (also turn off "Sanning always available" in WiFi advanced settings).
2. Turn off auto sync.
3. Change the network mode to 2G.
4. Turn off mobile data.
5. Disable any screensavers/live wallpapers and use any black coloured wallpaper.
6. Disable phone vibration.