Install mpc and ncmpc
Command line tools to manage mpd
Install pre-built packages:
 $ sudo pkg_add mpc ncmpc

mpc is very simple:
Play:			mpc play
Stop:			mpc stop
Pause:		mpc pause
Next:			mpc next
Status:		mpc status (or, simply mpc)
Update music db:	mpc update

You can also manage playlists, but I'm still learning how.

ncmpc is an ncurses (text-based GUI) interface to mpd.  It is feature
limited, but the features is does support are easy with the GUI.