rework requirements page

docs/requirements.md

@@ -8,13 +8,27 @@
 
 ## Requirements
 
-- Source Machine:
-  - Can be any Linux or Mac computer with Nix installed, or a NixOS machine.
-- Destination Machine:
-  - Must be an x86-64 machine unless you are able to supply a `kexec` image for
-    your CPU type.
-  - If you're not using the option to boot from a Nixos installer image, it
-    must:
-    - Be running x86-64 Linux with kexec support . Most x86_64 Linux systems do
-      have kexec support.
-    - Have at least 1.5 GB of RAM, excluding swap.
+### Source Machine:
+
+1. **Supported Systems:**
+   - Linux or macOS computers with Nix installed.
+   - NixOS
+   - Windows systems using WSL2.
+
+2. **Nix Installation:** If Nix is not yet installed on your system, refer to
+   the [nix installation page](https://nixos.org/download#download-nix).
+
+### Destination Machine:
+
+1. **Direct Boot Option:**
+   - Must be already running a NixOS installer.
+
+2. **Alternative Boot Options:** If not booting directly from a NixOS installer
+   image:
+   - **Architecture & Support:** Must be operating on:
+     - x86-64 or aarch64 Linux systems with kexec support. Note: While most
+       x86-64 Linux systems support kexec, if you're using an architecture other
+       than those mentioned, you may need to specify a
+       [different kexec image](./howtos.md#using-your-own-kexec-image) manually.
+   - **Memory Requirements:**
+     - At least 1.5 GB of RAM (excluding swap space).