There are some great tools for Windows computers that make it easy to root the Google Nexus 7 tablet, unlock, the bootloader, or install a custom recovery. But what if you’re a Mac user?
There’s an app for that.
Xda-developers forum techfanatic9 has put together a  Mac Toolkit for Google Nexus 7 users.
The toolkit lets you:
- Root the tablet
- Unlock the bootloader
- Install ClockworkMod Recovery
You can also use it to undo and of those things. So if you want to remove root and go back to the stock Android 4.1 firmware, you can do that. You can also lock the bootloader again.
There are different scripts for different actions, so only have to download the ones you need.
I am using the Windows one, I used this tutorial and it worked!
https://tutznet.com/nexus-7-toolkit-root-backup-install-recovery-lot.html