Some setup you must do manually if you haven't yet:

1. Register your Rails application on: https://dashboard.stripe.com/register
2. Update the stripe PUBLISHABLE_KEY in "config/initializers/stripe.rb"
   For example:

   Stripe.api_key = ENV['STRIPE_SECRET_KEY']

3. Update stripe PUBLISHABLE_KEY in the "views/stripe/checkouts/create.js.erb"
   For example:

   var stripe = Stripe(ENV["STRIPE_PUBLISHABLE_KEY"]);

4. Update "controllers/stripe/checkouts_controller.rb" with stripe checkout
   line_items, success and failure callback URLs.

5. Go to: http://localhost:3000/stripe/checkout and try the checkout flow.