Lenovo A1000

At the beginning switch off the cell phone by holding the Power button.Hard Reset LENOVO S650
Hold down the Volume Up + Volume Down+ Power simultaneously for a couple of seconds.HardReset LENOVO S650
You can release held keys when you see a Lenovo Logo.
The Recovery Mode menu should appear on your screen.Master Reset LENOVO S650
Press Volume Down to choose "wipe data/factory reset", and then push the Power button to confirm.
Select "Yes--delete all user data". Use Volume Down button to scroll and Power key to select.
To restart the phone, select "reboot system now".
Success! The hard reset is done!
Second method:
Turn on the phone by using the Power button. Hard Reset LENOVO S650
Go to Settings and then to Backup & Reset.
Tap Factory data reset.
Choose Reset phone and select Erase everything.
Well done! Your phone should restart.