Install nix:
curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh -s -- install
Install home manager:
nix-channel --add https://nixos.org/channels/nixpkgs-unstable
nix-channel --add https://github.com/nix-community/home-manager/archive/master.tar.gz home-manager
Update the channels:
nix-channel --update
nix-shell '<home-manager>' -A install