1. gem file

gem ‘rails_admin’, ‘~> 0.7.0’

2. install

rails g rails_admin:install

3 .if rails_admin

bundle exec rails generate paper_trail:install –with-changes –with-associations

4. if WillPaginate

In your config/initializers/kaminari.rb,

if defined?(WillPaginate)
  module WillPaginate
    module ActiveRecord
      module RelationMethods
        def per(value = nil) per_page(value) end
        def total_count() count end
      end
    end
    module CollectionMethods
      alias_method :num_pages, :total_pages
    end
  end
end