[README] Include howto and docs.

README.md

@@ -1,3 +1,62 @@
-# screenrecord
+# Screen Record
 
-A useful screen recording script for sway.
+`screenrecord.sh` is a mindless, yet useful,
+script to record your screen in [sway](https://swaywm.org).
+
+Really, it doesn't do anything else.
+
+# Why?
+
+Because I had enough to bring up a shell, use tiresome aliases,
+or, god forbid, fire OBS Studio to just record my screen.
+
+I wanted a simple keyboard shortcut to toggle screen recording on and off at will,
+and I have the impression other people may wish the same.
+
+# Does it depend on anything?
+
+Yes, to use `screenrecord.sh` you need:
+
+* [wf-recorder](https://github.com/ammen99/wf-recorder) for the actual screen recording functionality.
+* [mako](https://github.com/emersion/mako), or any other notification manager that may be triggered via `notify-send`.
+* [jq](https://stedolan.github.io/jq) to parse JSON from command line.
+* [slurp](https://wayland.emersion.fr/slurp/) to select a screen area.
+
+These lovely utilities are often already available on many `sway` setups.
+
+# How do I use it?
+
+1. Either clone the repo or copy the latest `screenrecord.sh`
+   somewhere in your home. For the sake of this example, let's assume you
+   placed `screenrecord.sh` in some `$HOME/bin` directory.
+
+2. Customize your `~/.config/sway/config` and register some shortcuts
+   to record your screen, e.g.:
+   ```
+     set $screenrecord "$HOME/bin/screenrecord.sh"
+     bindsym $mod+r exec $screenrecord -t
+     bindsym $mod+Shift+r exec $screenrecord -wt
+     bindsym $mod+Control+r exec $screenrecord -st
+   ```
+   You should now be able to record your screen with those shortcuts.
+
+3. If you're using a status bar (e.g. [i3status](https://github.com/i3/i3status)),
+   you can easily customize it to react to `screenrecord.sh` pidfile,
+   for example in your `~/.i3status.conf`:
+   ```
+     order += "run_watch screenrecord"
+
+     run_watch screenrecord {
+       pidfile = "/var/run/user/1000/screenrecord.pid"
+       format = "🎥"
+       format_down = ""
+    }
+   ```
+
+# License
+
+Public domain, enjoy this code at will and use it at your own risk.
+
+See [unlicense.org](https://unlicense.org/) for details or read the `LICENSE` file.
+
+Cheers :)