This project was tested with summernote-rails gem in Rails 4.0 project.
I greatly appreciate Summernote Development Team.
Of course, you can use summernote editor without summernote-rails gem, but it is a hassle.
With summernote-rails gem, you just add this in gemfile and bundle install as usual.
Afterwards, you can easily understand how to use summernote editor in Rails project, with this test project.
Summernote-rails URL: github.com/rorlab/summernote-rails
Thank you.