There are a few prerequisites you will need first:
-- Xcode 4 (install from the AppStore)
-- Command Line Tools (install from Xcode 4 -> Preferences -> Downloads)
+- Xcode 5 (install from the AppStore)
+- Command Line Tools (install from Xcode 5 -> Preferences -> Downloads)
- MacPorts (http://www.macports.org/install.php)
or
- Homebrew (http://mxcl.github.io/homebrew/)