Thus an independent rooting seems to be cool for you.
[STEP I] Ensuring that you've these elements below
(a) An tether by microUSB to USB
(b) An most recent Samsung driver: http://forum.xda-developers.com/showthread.php?t=961956
(c) SuperSU binary (http://download.chainfire.eu/382) & app (Play Store) v1.93
(d) Good network connections & turning off the entire security softwares
(e) An Odin you think it isn't old & works
(f) An most recent TWRP: http://teamw.in/project/twrp2/196
[STEP II] Setting up rooting elements
(a) Extract Odin archive into C:/Android then open Odin
(b) Unboot tethered Crater & reboot it into Odin bootloader by keys 'home' & 'vol minus'
(c) Place TWRP into PDA field w unchecking the entire options to lose nothing in Odin
(d) Are patient at this process
(e) Untether Crater since passing this process then power off Crater
[STEP III] Flashing SuperSU
(a) Reboot unbooted Crater & reboot it into TWRP by keys 'home' & 'vol plus'
(b) Click 'install' & select the binary
(c) Are patient at this process
(d) Reboot Crater since passing this process then open SuperSU app
(e) WELL DONE!!
(f) Install an firmware by Odin as well as an official repair
(g) Reflash TWRP then reroot repaired Crater by repeating first 5 minor steps
[EXTRA] How abt the other brands
The majority of steps are the same.
The only difference is the proper USB driver & tool acdg to your brand
THANKS FOR YOUR HAVING FUN. I'M FREE TO BE GIVEN FEEDBACKS.