First: I write the article in *.mdown format.

Coda Screenshot

Second: I check on my computer everything works fine.

shotgun config.ru

Nesta Server Screenshot

Third: login in heroku.

heroku login

Fourth: update the code from server.

git pull

Fifth: send to git server the changes.

git add .

git commit -a -m “How to publish”

Sixth: send to heroku server.

git push heroku master

More information about Heroku git in this page.