Update README.md

Author: ishan-biztech

README.md

@@ -1,11 +1,45 @@
-# Rollbar plugin for CakePHP
+# Rollbar plugin for CakePHP 3.x
+
+CakePHP plugin integration for Rollbar error tracking tool.
+
+## Requirements
+
+- CakePHP 3.5 or greater
+- PHP 5.6 or greater
+- And [Rollbar](https://rollbar.com/) account
 
 ## Installation
 
-You can install this plugin into your CakePHP application using [composer](https://getcomposer.org).
+1. You can install this plugin into your CakePHP application using [composer](https://getcomposer.org)
 
-The recommended way to install composer packages is:
+    ```
+    composer require ishan-biztech/cake-rollbar
+    ```
 
+2. After installation, [load the plugin](https://book.cakephp.org/3/en/plugins.html#loading-a-plugin)
+    ```php
+    // src/Application.php
+    Plugin::load('Rollbar');
+    ```
+    Or, you can load the plugin using the shell command:
+    ```sh
+    bin/cake plugin load Rollbar
+    ```
+
+## Setup
+
+Create a new Rollbar project and get `post_server_item` access token by going to your project's settings. And set below config array into your `config/app.php` file.
+
+```php
+// config/app.php
+return [
+    'Rollbar' => [
+        'access_token' => env('ROLLBAR_POST_SERVER_ITEM_ACCESS_TOKEN', null),
+        'environment' => env('APP_ENV'),
+    ]
+];
 ```
-composer require ishan-biztech/cake-rollbar
-```
+
+All set! :tada:
+
+This plugin will capture and send all the notices, errors, exceptions, etc. to Rollbar for you to solve them.