1. Add the gem to Gemfile.
group :development do
gem 'web-console', '2.0.0.beta3'
3. You can go to the web console by going to the URL : http://localhost:3000/console
You will also see the web console on the bottom of the browser. You can experiment with the Rails environment loaded.
4. You can add "<%= console %>" to any views and play with the web console.
If you restart the server. You need to reload the page to get a new active console session.
For more details : Web Console Ruby Gem