Helpful usage instructions:
http://gravityblast.com/2009/07/30/2-minutes-admin-layout-with-rails-and-the-web-app-theme-generator

Much more detailed tutorial is available here:
http://blog.bryanbibat.net/2011/09/24/starting-a-professional-rails-3-1-app-with-web-app-theme-devise-and-kaminari/

If you want two column forms, making forms 2 columns