Hard Reset HUAWEI Ascend Mate 7

First method:

1. Press Power button, until your device is off.
2. Then press and hold the Volume Down and Volume Up buttons.
3. While holding these buttons press the Power button for a while.
4. You can release held keys when you see an Andoid image.
5. Afterwards press Volume Down to choose "wipe data/factory reset", and then push theVolume Up to confirm.
6. By using Volume Down scroll to "Yes--delete all user data" and confirm that choice byVolume Up key.
7. To restart the phone, select "reboot system now".
8. Great job!

Second method:

1. Make sure that your phone is switched on. 
2. Then go to Settings and then to Backup & Reset.
3. Tap Factory data reset.and choose Reset phone.
4. Select Erase everything to confirm the whole operation.
5. Well done!

WARNING !
Hard Reset will erase all of your data
All described operations you are doing at your own risk.