Clarify argument documentation slightly

Author: jrouly

README.md

@@ -1,10 +1,14 @@
-Simple dmenu frontend for MPD.
+# mpdmenu
 
-# Arguments
+Simple [dmenu](https://tools.suckless.org/dmenu/) frontend for [MPD](https://www.musicpd.org/).
 
-Pass mpdmenu arguments first, followed by any dmenu arguments. They are separated by `::`. For example:
+### Usage
 
-    mpdmenu -p :: -sb '#000000'
+    $ mpdmenu [-p | -l] [:: DMENU_ARGS]
+         -p playlist mode, selects a track from the current playlist
+         -l library mode (default), descends artists and albums
+
+Additional arguments for `dmenu` can be passed after `::`.
+For example:
 
-`-l` is library mode (default), which descends artists and albums. `-p` is
-playlist mode, which selects a track from the current playlist.
+    mpdmenu -p :: -sb '#000000'