How to format or wipe Samsung Galaxy S II

First one is “Performing a factory data reset via settings” this is the normal method, this method we apply phone run normal.

1. Go to Settings.
2. Select Privacy.
3. Click on Factory data reset.
4. Check Format USB storage if needed only.
5. Click on Reset phone.
6. Finally, select Erase everything.

Second is “Performing a factory data reset using phone buttons” this method is we apply only phone is hang, or not responding, personally am use this method, its easy but little careful.
1. Turn off SGS2.
2. Press and hold down Volume Up + Home + Power buttons at the same time.
3. Release all buttons when you see SGS2 Logo.
4. Android system recovery will be loaded then.
5. Select wipe data/factory reset. (Volume buttons to go up or down, select with Home button)
6. Select Yes — delete all user data.
7. Finally, select reboot system now.
This method also a normal “Performing a factory data reset using dial pad”
1. Warning~ no turning back after key in.
2. Bring up dial pad.
3. Key in *2767*3855#
4. Finally, SGS2 will be rebooted and factory data reset.