Follow these in order and you will have a NAND backup of your switch, which is useful for going back to a clean slate if something weird happens.
An emuMMC set up with hekate, so all your "dirty" custom firmware stuff you do like installing game dumps, and/or cheats are kept there under incognito. Keeping you less likely from getting a console ban, where your sysMMC is used for legitimate games you have and Nintendo online.
If your console is already banned, there's no huge reason to use to use emuMMC, so you can skip that part of the guide.
Atmosphere and sigpatches, custom firmware that's used for loading homebrew apps (like Checkpoint for backing up your game saves) and installed dump games/apps (such as Tinfoil.) Sigpatches allow you to install game dumps, and run homebrew NSP applications that you normally wouldn't be able to.
(Optional) Tinfoil, useful for installing game dumps with "shops" added to it.