This quick guide assumes that you use
yaourt
for AUR package installation.
Just download cherrymusic straight from the AUR:
Minimal Installation (no optional dependencies)
yaourt -S cherrymusic
Full Installation (all optional dependencies)
yaourt -S cherrymusic lame vorbis-tools flac faad2 mpg123 ffmpeg python3-stagger-svn imagemagick
More details
The installation guide in this site has some more specifics.
For a nice system integration and configuration proposals there is a very detailed setup guide in the arch linux wiki that contains much more useful information