docs: README

README.md

@@ -1,6 +1,6 @@
 # 🎵 bum
 
-`bum` is a daemon that downloads album art for songs playing in `mpd` and displays them in a little window. `bum` doesn't loop on a timer, instead you can send it `SIGUSR1` to get it to download album art for the current playing track. This makes `bum` lightweight and makes it idle at `0%` cpu usage.
+`bum` is a daemon that downloads album art for songs playing in `mpd` and displays them in a little window. `bum` doesn't loop on a timer, instead you can send it `SIGUSR1` to make it wake up and download album art for the current playing track. This makes `bum` lightweight and makes it idle at `~0%` CPU usage.
 
 Note: `bum` is meant to be used with files that don't have embedded album art (`mopidy-spotify`).
 
@@ -21,3 +21,34 @@ Note: `bum` is meant to be used with files that don't have embedded album art (`
 ```py
 pip install bum
 ```
+
+
+## Usage
+
+```sh
+usage: bum [-h] [--size "px"] [--cache_dir "/path/to/dir"] [--version]
+
+bum - Download and display album art for mpd tracks.
+
+optional arguments:
+  -h, --help            show this help message and exit
+  --size "px"           what size to display the album art in.
+  --cache_dir "/path/to/dir"
+                        Where to store the downloaded cover art.
+  --version             Print "bum" version.
+```
+
+
+## Customization
+
+### ncmpcpp
+
+You can configure `ncmpcpp` to send `SIGUSR1` to `bum` on every song change.
+
+
+```
+# .ncmpcpp/config
+
+# Execute bum on song change.
+execute_on_song_change = "pkill -USR1 bum"
+```