WARNING! This is just what worked for me, and it's just the adb commands from thecubed's program. All credit goes to him, I didn't do any of this, just took the info from it.
Here's the thread: http://forum.xda-developers.com/show....php?t=2448887
Download it, unzip it, and then take a moment to go back and thank him if you didn't do that.
You are not actually using his program, just the files and commands. Everything is done using Terminal and the Finder. You must have ADB working, look elsewhere for instructions on setting that up.
The files used here are the Verizon versions of the files, which I used for my phone. They are also specific to the OTA'd Verizon software, "11A" so there are different files if you haven't installed the OTA. These commands are correct, but the files being pushed aren't all the same between different carrier models and do not work with any other carrier. All the right stuff for other carriers is contained in thecubed's program.
The bold sections are files you need to send over adb, you can manually enter the file pathway or drag the files from finder into terminal after the adb commands (and before you type the destinations).
One more warning; if this is your first time using adb or terminal, I don't recommend this as your first try. It's super easy to screw something up in terminal.
Your phone must have developer options enabled and usb debugging on. plug in your phone via usb and select "Internet" and then "Ethernet."
adb push ytiruces_1a_vzw
Unplug usb, disable USB debugging and then re-enable it. Plug USB back in.
adb shell "mount -o remount,rw /system"
adb push su
adb shell "chown 0.0 /system/xbin/su;chmod 06755 /system/xbin/su;sync;mount -o remount,ro /system"
adb install superuser.apk