Under : http://www.wugfresh.com/dev/gnex-root-toolkit/
Instructions:
Do not plug in your device until this program prompts you too!
Install the program by double clicking the GnexRootToolkit.sfx.exe
This will extract the contents to %HOMEDRIVE%\Wugs_GnexRootToolkit
Place a shortcuts on your Desktop
Launch the program for first use
Use the “Drivers” option to make sure all your drivers get configured properly.
This is a crucial step. Nothing else will work otherwise, so make sure your drivers are properly configured before you try doing anything else with this program.
Follow the onscreen driver instructions carefully and you should have no problems.
Use the “Backup Apps + Data” if you want to preserve your apps and settings for restoration after you unlock and root.
Then use the “Unlock” to unlock and the “Root” to root… Tada! Enjoy your unlocked and rooted device. ^_^
Then whenever you need to go back to square one just use the “Flash stock + Unroot” and “OEM lock” features.
Remember that this option can also be used if you completely brick.
This should bring you back to a fully locked stock factory state.