OK. We've got an empty app and it has been added to git. What now? Ship it!
In your terminal, try:
$ heroku create
$ git push heroku master
$ heroku open
heroku create registers a new application on heroku's system.git push takes all changes you've committed locally and pushes them to heroku.heroku open opens the new application in your browser.While I realize that at this point this isn't all that exciting, the point is that it doesn't get more difficult than this as we add more functionality to the application. Your typical process will look like:

git commit -m "msg" filesgit push heroku masterand boom! Your changes are live!