2FS Notes Below:
Before formatting ALL your partitions to F2FS keep in mind that due to F2FS's performance drop of Sequential Reads (when compared to EXT4) it may be better to leave /system as EXT4. Still its your choice and may find it runs better! With /system you mainly are reading from it than writing. Note that you cannot format /system UNLESS the Rom supports it! Also DO NOT format any other partitions other than:
/system
/data (this will format userdata too FYI)
/cache
The steps I used:
1. Backup EVERYTHING on your Internal Memory to another device (Pro Tip - Use an app like SD Maid and get rid of orphaned data first, could save you alot of time/space)
2. Boot into a F2FS enabled recovery - I use this one: [TWRP][2.8.4.0][2015.01.13][BUMPed] TWRP w/ Thermal & F2FS
3. Format the Desired partition to F2FS:
* Go to Wipe
* Select Format Data
* Select Advanced Wipe - Only select one partition at a time or you will get an error!
* Select Repair or Change File System
* Select Change File System
* Select F2FS
4 Now that you have formatted your desired partition Connect your phone back up to your back up Device. For me it was a computer then:
* Go to Mount
* Enable MTP
This should allow you to mount your phone while connected to a computer. I had issues with it mounting properly. It would show up but I couldn't add anything to it. I found that I needed to install the proper drivers for it to mount properly. For me I used Google Composite ADB Drivers. After that I just had to Reboot back into Recovery.
5. Now that you are mounted properly, go ahead and copy your files back so you can flash a rom and get back up and running. Also, if you made a backup and did not format /system, once you copy your TWRP files back you can restore from that backup.