[Galaxy Note 4 Q&A, Help & Troubleshooting] uktechguru:
Yeah you got it. That's the safest way to do it.

---------- Post added at 08:58 PM ---------- Previous post was at 08:11 PM ----------

Best way is to use chainfire's root file which can be found at

http://download.chainfire.eu - find your phone. Only a number of note 4 versions are supported.

You need to have stock rom on your note 4 and then go into Odin and flash the root file as PDA file or whatever it says in the second box on the right (sometimes it says something different depending on what version of Odin you have).

Once you've rooted, to confirm your phone has toured successfully, download

https://play.google.com/store/apps/details?id=com.joeykrim.rootcheck

Open the app and let it check if you're rooted. If you are, you can install ROMs.

Install flashify from play store and use that app to install TWRP (custom recovery).

You should note that some ROMs only support certain phone models and android versions. Cyanogen is supported on only a couple of note 4 models (sm-n910g and sm-n910f). You can only run ROMs that are for the specific android version that you have on your phone, ie lollipop or KitKat etc.

If you have sm-n910f like me you can download the recent nightlys but they're a little unstable at the moment with some bugs. Cyanogen haven't got to a stable stage yet with cm12 lollipop.

CM12 nightlys can be found at

http://download.cyanogenmod.org/?device=trltexx

You just need to download the latest version to your phone then shut down your phone completely and go into recovery by pressing volume up+home+power. This will load TWRP custom recovery.

Now select install (top left option) and find the place where you downloaded the software (usually in download folder). Select the software then it'll take you to another screen where it will confirm the file to be flashed and it will have with an option at the bottom which days "swipe to confirm flash" to install. It should start installing now. Once it's completed and you get a "success" message, select "reboot system" and it should reboot. It will take a while to complete first boot. You should get a white box saying "asbestos is upgrading". Once it's done you should have cm12.

To update, you can either go into the settings and about phone and choose cyanogenmod updates. They're usually done every night and using this option will automate the update process (it will reboot into recovery itself and complete the install and reboot the system back up after it's complete - just be aware, sometimes it won't work when it gets to recovery. I've found it stopped when recovery is loaded and I've had to complete the rest myself). Alternatively you can go to the website I gave you above and download directly from the site and complete the install as above. As you'll have cm12 installed at this point, you can just press and hold the power button until the options come up and select "reboot" and then "recovery".

The above method is called " dirty flashing ". If you want a complete clean install then at the point you go into TWRP recovery, choose the option to wipe option and then slide the bar where it says " Swipe to factory reset ". Once that's done you can install the software as above.

I would strongly suggest that you do a backup before you do any of this. Once you've rooted, you can go into recovery and select "backup" and swipe to backup. It takes a while for backup to complete. One you've backed up then you can continue as above. In the even you get any errors, you can restore using recovery.

Other ROMs are usually flashed through recovery but I would suggest you read before hand to confirm the method. Flashed in the same way as above or alternatively you could use the flashify app which will help automate a bit better like using the update option in the settings.

You need to be aware that on cyanogen you'll loose all s pen functions and other functions that are exclusive to the note 4.

This is the thread for cm12 on sm-n910g and sm-n910f

http://xdaforums.com/showthread.php?t=3046965

Hope this makes sense!