If you can get into the tablet:
1.Click/Tap the settings
2.Choose the privacy
3.Click/tap the reset phone
4. Select Erase Everything
5.After that your device will be wiped and it will be a factory fresh state
6.From the home screen,tap the menu
7. Select settings
8.Select Reset and back up
9.Choose factory data reset
10.Tap Reset device
If you cannot get into the device
1. Turn off your tablet
2. Press Volume Up + Power Button + Home
3. Recovery Menu would be up by now
4. Scroll down and Find " Wipe Data/ Factory Reset"
5. Click next , Scroll down until you find " Yes-- Delete all data "
6. Confirm and Reboot your tablet.
7. on a reset you will need to enter the password for your google account that was used to login originally on the tablet