Once you're ready to access your application with a web browser, start up the Padrino server. This is done by issuing the command padrino start from the command line in the root directory of your application. If everything is working correctly, the Padrino server will start up and bind to port 3000 on your localhost. Try opening a web browser and going to http://localhost:3000/hello.
If you get an error message when trying to start Padrino, scroll to the top of the errors and see if there's a missing Gem. This is a common error, simply run the command bundle install and try again.