You can use this as a start point for managing a WordPress install with git.
See 'Install and manage WordPress with Git' for more details.
You can either run:
rake
Or manually run:
git submodule update --init
Then copy wp-config-sample.php to wp-config.php, update your database settings, and your default theme.
You can use the Rake helper task to upgrade WordPress to a specific version:
rake wordpress_update[3.7.1]