Simple Install
1. Login to WordPress and go to Plugins > Add New > Upload
2. Upload foobox-free.zip and activate
3. FooBox should work out of the box with any linked images
4. Goto Settings > FooBox Settings to change the default configuration

Manual Install
1. Upload the foobox-free folder to your /wp-content/plugins/ directory.
2. Activate the plugin through the 'Plugins' menu in WordPress.
3. FooBox should work out of the box with any WordPress Gallery
4. Goto Settings > FooBox Settings to change the default settings