register your app, see instructions: https://gist.github.com/darbula/5003f1d2e1528b089b30#obavezni-koraci-koji-nisu-vezani-uz-django
clone Rails sample app provided by good people from OneLogin Inc.
git clone https://github.com/onelogin/ruby-saml-example.git
edit file app/model/account.rb
to reflect your consumer service endpoint