For the adventurous type.
This for the LTE N9005 version.
NB: You will void your warranty.
NB: You may brick your phone.
1. Download CF-Root
http://download.chainfire.eu/352/CF-Root/CF-Auto-Root/CF-Auto-Root-hlte-hltexx-smn9005.zip and extract.
2. Download Odin
https://hotfile.com/dl/196702311/668088d/Odin307.zip.html and extract.
3. Go Settings / General / Security and switch off Reactivation Lock.
4. Reboot into download mode (Power off, press and hold Vol Down + Home + Power. Select Vol Up when prompted).
5. Launch Odin (from step 2 above) as Administrator. If you cannot see your device connected in one of the blocks at the top, then install Kies or
https://rapidshare.com/files/416304166/SAMSUNG_USB_Driver_for_Mobile_Phones.exe and try again.
6. Make sure Auto Reboot and F.Reset Time are ticked. Leave other settings alone.
7. Click PDA and select CF-Auto-Root-hlte-hltexx-smn9005.tar.md5 from step 1 above.
8. Click Start.
If you break your phone, don't complain to me. This is done entirely at your own risk!
The CF-Root package comes with Odin 1.85. I never used that though. I went with the Odin from step 2.