Added Better Errors in README.md

README.md

 # Getting Started with Rails, Docker
-## Usage
+## Setup
 *  Clone this repository
 
 ```bash
@@ -101,8 +101,36 @@ production:
   password: <%= ENV['RAILS_DATABASE_PASSWORD'] %>
 ```
 
-* Create the ``development`` and ``test`` database
+* Create the ``development`` and ``test`` databases
 
 ```bash
 docker-compose run web rails db:create
+```
+
+## Adding [Better Errors](https://github.com/charliesome/better_errors) gem
+
+* In ``Gemfile``, add these gems under ``development`` group.
+
+```bash
+group :development do
+  ...
+  
+  gem 'better_errors'
+  gem 'binding_of_caller'
+end
+```
+
+* Run this command to setup Better Errors initializer file.
+
+```bash
+touch config/initializers/better_errors.rb
+```
+
+* Open ``config/initializers/better_errors.rb``.
+* Add this code in ``config/initializers/better_errors.rb``
+
+```bash
+if Rails.env.development?
+  BetterErrors::Middleware.allow_ip! "0.0.0.0/0"
+end
 ```
\ No newline at end of file