First instruction
1. First of all, take off the phone's back cover and remove the battery.
2. Wait a few seconds and reassemble the phone. Lastly, press the Power button to turn it on. Done!
Second instruction
1. Hi. Start by pressing and holding the Power button. Release it when a menu appears on screen.
2. Next, select the Power off option.
3. Press & hold the Power button until the phone turns back on. Well done!