Rooting is just the process of getting root-level access to your build's file system. This is obtained by placing two files in your /system directory. With an unlocked bootloader, this is easily accomplished.
Assuming you already have fastboot.exe on you computer (found in the attachment in the first post) and the drivers set up on your PC, do the following:
1) Download (to your computer) the appropriate version of CWM for your device (or TWRP
if you so desire). If you have a GSM version, use this
one. If you have a Verizon device, use this
one, if you have a Sprint device, use this
2) Rename the file to cwm.img, and make sure it is in the same directory as your fastboot.exe file;
3) Download (to /sdcard on your device) the latest version of [strike]either Chainfire's SuperSU
or Koush's Superuser
4) Restart your device in fastboot mode and plug into computer
5) Open a command prompt in the directory mentioned above and type: fastboot boot cwm.img
6) Wait for it to boot
7) Navigate the menus the CWM menu on your device and select an option like "update zip from sdcard". Find the zip that you downloaded, and apply it.
8) Reboot. Done.
And no, this procedure does not flash CWM to your device.