docs: make nix-channel choice more clear

README.md

@@ -63,22 +63,21 @@ Currently the easiest way to install Home Manager is as follows:
 
     Note that Nix 2.4 (`nixUnstable`) is not yet supported.
 
-2.  Add the appropriate Home Manager channel. Typically this is
+2.  Add the appropriate Home Manager channel. If you are following
+    Nixpkgs master or an unstable channel you can run
 
     ```console
     $ nix-channel --add https://github.com/nix-community/home-manager/archive/master.tar.gz home-manager
     $ nix-channel --update
     ```
 
-    if you are following Nixpkgs master or an unstable channel and
+    and if you follow a Nixpkgs version 20.09 channel you can run
 
     ```console
     $ nix-channel --add https://github.com/nix-community/home-manager/archive/release-20.09.tar.gz home-manager
     $ nix-channel --update
     ```
 
-    if you follow a Nixpkgs version 20.09 channel.
-
     On NixOS you may need to log out and back in for the channel to
     become available. On non-NixOS you may have to add
 

doc/installation.adoc

@@ -37,8 +37,9 @@ must be covered by the {nix-allowed-users}[`allowed-users`] Nix
 option. On NixOS you can control this option using the
 {nixos-allowed-users}[`nix.allowedUsers`] system option.
 
-2. Add the Home Manager channel that you wish to follow. This is done
-by running
+2. Add the Home Manager channel that you wish to follow. If you are
+following Nixpkgs master or an unstable channel then this is done by
+running
 +
 [source,console]
 ----
@@ -46,7 +47,7 @@ $ nix-channel --add https://github.com/nix-community/home-manager/archive/master
 $ nix-channel --update
 ----
 +
-if you are following Nixpkgs master or an unstable channel and
+and if you follow a Nixpkgs version 20.09 channel, you can run
 +
 [source,console]
 ----
@@ -54,8 +55,6 @@ $ nix-channel --add https://github.com/nix-community/home-manager/archive/releas
 $ nix-channel --update
 ----
 +
-if you follow a Nixpkgs version 20.09 channel.
-+
 On NixOS you may need to log out and back in for the channel to become
 available. On non-NixOS you may have to add
 +
@@ -111,7 +110,8 @@ deployed through NixOps.
 
 To make the NixOS module available for use you must `import` it into
 your system configuration. This is most conveniently done by adding a
-Home Manager channel, for example
+Home Manager channel. For example, if you are following Nixpkgs master
+or an unstable channel, you can run
 
 [source,console]
 ----
@@ -119,7 +119,7 @@ Home Manager channel, for example
 # nix-channel --update
 ----
 
-if you are following Nixpkgs master or an unstable channel and
+and if you follow a Nixpkgs version 20.09 channel, you can run
 
 [source,console]
 ----
@@ -127,8 +127,6 @@ if you are following Nixpkgs master or an unstable channel and
 # nix-channel --update
 ----
 
-if you follow a Nixpkgs version 20.09 channel.
-
 It is then possible to add
 
 [source,nix]
@@ -190,7 +188,8 @@ tool.
 
 To make the NixOS module available for use you must `import` it into
 your system configuration. This is most conveniently done by adding a
-Home Manager channel, for example
+Home Manager channel. For example, if you are following Nixpkgs master
+or an unstable channel, you can run
 
 [source,console]
 ----
@@ -198,7 +197,7 @@ Home Manager channel, for example
 # nix-channel --update
 ----
 
-if you are following Nixpkgs master or an unstable channel and
+and if you follow a Nixpkgs version 20.09 channel, you can run
 
 [source,console]
 ----
@@ -206,8 +205,6 @@ if you are following Nixpkgs master or an unstable channel and
 # nix-channel --update
 ----
 
-if you follow a Nixpkgs version 20.09 channel.
-
 It is then possible to add
 
 [source,nix]