EDIT: DO NOT UPDATE TO 6.2.0.

Spoiler: More Info

6.2.0 currently breaks all CFW.
If you did by accident I hope you have backups to restore to! Last safe version is 6.1.0, I recommend staying on 5.1.0 if possible, you should be able to all or most current titles if you install with tinfoil using the ignore minimum required firmware option.
Use 90DNS to block connections to Nintendo so you don't get asked to update, even banned consoles will be prompted to update.
If you did accidentally update without a backup, backup your 6.2.0 console then try to downgrade with Choidujour.

I highly recommend backing up your NAND in case you mess up your switch, it's much easier than most would think.
I hope to make it even more simple with this guide. Backing your switch up doesn't need to be hard or resource heavy with the right know how.
Yes some of this might be common knowledge to some, but we all have to learn these things from somewhere and maybe there will be one or two things to pick up from here even if you are an expert.
This is supposed to be an easy and simple guide for those who haven't yet to help encourage more people to make backups so they don't make expensive paperweights out of their consoles.

NAND BACKUP

Spoiler: Quick and simple guide for backing up with Hekate

https://guide.sdsetup.com/#/configuringhekate

You can also use the ReiNX Toolkit to dump your NAND (same as backing up your "eMMC RAW GPP" with Hekate), Boot0, and Boot1 (same as backing up your "eMMC BOOT0/1" with Hekate).
These are the files that your backup should consist of and will be all you need to restore your switch in most cases.
Just keep in mind you can't restore with the toolkit and will still need to use something like Hekate to restore your NAND, Boot0, and Boot1.

BACKUP INTEGRITY
After you've copied your backups somewhere I recommend you make a "Simple File Verification" (*.SFV) file, which does as you would think.

Spoiler: Quick guide on how to install QuickSFV and use it to do as such

[Main Article/Guide Page] https://www.newsgroupreviews.com/quicksfv.html
- [Installation] https://www.newsgroupreviews.com/quicksfv-installation.html
- [Making *.SFV Files] https://www.newsgroupreviews.com/quicksfv-create-sfv.html
- [Verifying with *.SFV Files] https://www.newsgroupreviews.com/quicksfv-how-to.html

We basically want to make a *.SFV file using a tool like QuickSFV so we can use the *.SFV file we made to validate whether or not our backup files are corrupt.
Files can go corrupt from things like drive failure, transfer errors, network issues during download/upload, etc.
It's important that we can make sure our backup files aren't corrupt when we need them.

BACKUP COMPRESSION
Last step (which suggest doing to save a lot of storage space) is compressing the files you backed up AND the SFV file you made earlier to a zip (quickest), rar (safest, moderately fast, good compression) or 7zip archive (highest compression/smallest archive size, but slowest compression/decompression speed).

Spoiler: Choosing the compression method that's best for you

- I suggest compressing to a zip file (use 7zip or your system's built in file manager) if your computer is slow or you just don't want to spend much time.
- 7zip (LZMA2) is the best making the absolute smallest size archives, but the difference isn't that large, and the performance costs for compressing/decompressing is much larger. I only recommend this if you have a high end computer with a good amount of RAM and a decent CPU or if you have a lot of time to spare.
https://www.7-zip.org/
- I like RAR (use WinRAR for this) best for making "safe" backups because you can add a recovery record which is useful for recovering/repairing your data in the event something bad happens (e.a. corrupt data from transfer), I suggest using at least a 3% record which should only take up to around 10-15mb of extra storage space.
https://www.rarlab.com/download.htm

If you don't know what to pick I suggest just compressing with WinRAR to a RAR (fast setting) with a recovery record between 2% to 5%.
I was able to easily compress my 32gb backup to just over 400mb WITH a 3% recovery record using the fast compression setting (solid, 1gb dictionary, use a smaller dictionary if you don't have much ram).

EXTRA STEPS/CONCLUSION

Spoiler: Testing, Validation, and Storage

Extract the archive you made somewhere to test and verify the files with the extracted *.SFV file if you want to be extra careful and see if the archive is good.
Once that's done you can deleted everything but the archive you've made, you only need the archive you've made now and just need to extract the archive if you ever do need your NAND backup files.
You can also create a *.SFV file for the archive you've made to validate the archive itself before extracting since the archive can also get corrupted when downloading/uploading/transferring data.

Keep and copy your archive to multiple places for safe keeping, it will relatively be a much smaller file now and can easily be stored to a USB drive, or uploaded online to somewhere like Dropbox, Google Drive, pCloud, Mediafire, MEGA, OneDrive, Zippyshare, Box etc.

Hopefully by now you have something like this (Google Drive)

or this (OneDrive)

All these steps took a little over half hour all together for me, and will be a lot less for you if you've already dumped your NAND from Hekate.
If you followed all these steps, you'll have your NAND backed up safely and easily to a lot of places with a lot of methods to verify integrity while taking up minimal storage space.

Too hard or too many steps for you?

Spoiler: Do the bare minimum (3 easy steps) to save storage space

WINDOWS
1. Right-click the folder containing your backup files.
2. Mouse over "Send to" then click "Compressed (zipped) folder"
3. I lied, it was just 2 steps. That's it, your backup files are now stored to a zipped folder and will take up much less space.

 

[shano]

I uninstalled the games i had on NAND memory then made another NAND backup and the zip compressed to about 24gb. =/

 

[romulopereira]

I uninstalled the games i had on NAND memory then made another NAND backup and the zip compressed to about 24gb. =/

When you Uninstall a game all you do is delete the entry in the system memory that says where all that files are and mark that space as available to new files. The data is there, the system just don't know where.

When you have a new switch all that nand is filled with 0s . It's make everything easier to the compression algorithms like zip, rar e 7zip.

I made my backup before installing anything. My nand compressed size is 500mb.

There's nothing you can do now to have a better compression in your nand.

An idea that could help people with the same problem as you is someone make a nsp with files filled with 0s to install in system nand. Like a big game that you install in your nand. That files would overwrite the hard to compress game files on the empty space with data easily compressible. You uninstall that game, make a backup and compression algorithms would theoretically be capable of doing their jobs better.

Unfortunately I don't have the skills to do it and don't even know if in a real world scenario it would work.

 

[Kubas_inko]

When you Uninstall a game all you do is delete the entry in the system memory that says where all that files are and mark that space as available to new files. The data is there, the system just don't know where.

When you have a new switch all that nand is filled with 0s . It's make everything easier to the compression algorithms like zip, rar e 7zip.

I made my backup before installing anything. My nand compressed size is 500mb.

Unfortunately, there's nothing you can do now to have a better compression in your nand.

He can do backup, format the console, backup again, compress new (second) backup, restore first one.
Idk if formating puts 0s everywhere tho.

 

[romulopereira]

He can do backup, format the console, backup again, compress new (second) backup, restore first one.
Idk if formating puts 0s everywhere tho.

I don't think it will work. The system format process is too fast for filling all nand with null data. Probably it's just a "fast format" that just reset the index of the partition.

 

[lemon07r]

Not sure if I did anything wrong but I used 7zip to zip up my back up and it only saved me 4gb (zipped up archive is 24 while unzipped is 29)

Is this all I can save ??

Zipping compresses the least amount but is much quicker that other compression methods. If you want to save more space compress to 7zip with lzma2 and solid compression or to a rar with winrar and solid compression. Using a larger dictionary size will also give you better compression (meaning smaller file size).

If you need more help let me know. Check out this guide for a more in-depth look at compressing with 7zip https://www.slideshare.net/mobile/LevanChelidze/7-zip-compression-settings-guide
Or if you want to compress to a *.RAR file just download and use WinRAR, compress to a rar file with the solid compression option selected.

Using RAR with the largest dictionary size, solid compression and fast setting will cut your file size down to around 400-450mb from 29gb. Using the best setting instead of fast will cut it down even further. Compressing to 7zip lzma2 with the best setting and solid compression will cut it down EVEN further but will take the longest time.

But there is a chance like the other's said that your backup doesn't have very much compressible data because there might have been other unsanitized data left behind after deletes in your nand before you backed it up.. I'd give trying better compression options a try anyways.

 

[GTRagnarok]

I made a new backup right after updating to a fresh 6.0.1. I had games installed prior on 4.1.0 and sure enough my new backup only compresses to 18GB. Need a way to zero out most of the nand.

 

[lemon07r]

I made a new backup right after updating to a fresh 6.0.1. I had games installed prior on 4.1.0 and sure enough my new backup only compresses to 18GB. Need a way to zero out most of the nand.

That's interesting. At least now we know. Maybe someone will make a tool for it in the future or add an option in to 0 blank space in nand backups.

 

[scroeffie]

i made a nand back up with autorcm on is that good or not do i leave it on or off
using sx os

 

[lemon07r]

i made a nand back up with autorcm on is that good or not do i leave it on or off
using sx os

I think it's fine unless you wanted a clean NAND for playing online with later in the future but I think you would want/have to disable autorcm for that anyways when and if you decide you want to try playing online with a clean NAND. Otherwise, if you don't care about any of that you're completely fine. Honestly I wouldn't really care about playing online if you're using CFW and homebrew anyways.

 

[noctis90210]

How about baking up fuses, kfuses, tsec and battery info? some tutorials backed it up? just curious it is mandatory or optional? thanks...

 

[Draxzelex]

How about baking up fuses, kfuses, tsec and battery info? some tutorials backed it up? just curious it is mandatory or optional? thanks...

Fuses and tsec are needed for kezplez-nx. So in reality, they are all optional.