Add a bit of info to the readme.

Author: ianmjones

README.md

@@ -1,4 +1,41 @@
 # wails-test
+
 A test of packaging a Wails app for Linux.
 
+## Makefile
+
+Check out the Makefile for annotated examples of how to build various targets, including...
+
+### tgz
+
+`make tgz`
+
+It's a very simple target for creating a *.tgz file.
+
+### flatpak
+
+`make flatpak`
+
+The `flatpak`, `flatpak-run` and `flatpak-install` targets show various ways to just test that a Flatpak can be built, build then run it, or build then install for the current user respectively.
+
+Because `flatpak-builder` does not allow build tools to download anything from the internet, it's pretty difficult to fully build a Wails project from source. This is discussed in Always Developing session #57:
+
+https://youtu.be/N6lvl4ePCYI
+
+The Flatpak manifest is at [flatpak/com.ianmjones.wails-test.yml](flatpak/com.ianmjones.wails-test.yml).
+
+### snap
+
+`make snap`
+
+The `snap`, `snap-debug` and `snap-prime-shell` targets show various ways to just build a snap, build and drop into a shell if there are problems, or drop into a shell just before it finishes so you can look at the files respectively.
+
+To see how the snapcraft.yaml was iteratively built, check out Always Developing session #59:
+
+https://youtu.be/prwJ0MfjnHQ
+
+The snapcraft template is at [snap/snapcraft.yaml](snap/snapcraft.yaml).
+
+---
+
 Originally built for https://github.com/wailsapp/wails/discussions/779