This covers the very basics of getting your Ruby on Rails application running on a Brightbox.
From the command line, run the deploy:initial Capistrano task:
cap deploy:initial
You'll receive email notifications from Monit that your system is working.
From then on, when you want to deploy new changes, just use the deploy task, or if you need to run new migrations use the deploy:migrations task.
Many of the other tasks available are documented in Capistrano Deployment Essentials. Lots more information about more advanced use of the Brightbox gem can be found in the user guide.