Questions regarding impermanence

I've been reading some articles regarding impermanence in NixOS, particularly this, this, this, and this, and I want to set up impermanence on my desktop system. Since it involves deleting my entire root, however, I figured I'd ask for advice here to learn what the best practices are for doing this to minimise risk of data loss, though it isn't too critical since it's a new setup. For reference, I have a Flake + home-manager setup on ZFS root, though I didn't think to do a snapshot when the disk was empty since I didn't know about impermanence when I started out. I also have separate ZFS datasets for /, /home, /nix, /var, and /var/lib. I want to set up impermanence for both root and home, with some persistent directories on home, but I'm not sure if I should set it up on both at once or if I should do root first and then home. Any advice or help is appreciated!