Add instructions

README.md

@@ -6,3 +6,47 @@ Lita::Adapters::Gitter
 [![Coverage Status](https://coveralls.io/repos/braiden-vasco/lita-gitter/badge.svg)](https://coveralls.io/r/braiden-vasco/lita-gitter)
 
 [Gitter](https://gitter.im) adapter for the [Lita](https://lita.io) chat bot.
+
+Usage
+-----
+
+At first, see the documentation for Lita: https://docs.lita.io/
+
+### Installation
+
+Add **lita-gitter** to your Lita instance's Gemfile:
+
+```ruby
+gem 'lita-gitter', '~> 0.0.0'
+```
+
+### Preparation
+
+Go to https://developer.gitter.im/apps, sign in if you are not already
+signed in, and remember your token.
+
+Then go to https://gitter.im/api/v1/rooms, find needed room by it's name
+and remember room ID which precedes room name.
+
+### Configuration
+
+#### Required attributes
+
+- `token` (String) - Secret token of Gitter user
+- `room_id` (String) - Room ID
+
+#### Example
+
+This is an example `lita_config.rb` file:
+
+```ruby
+Lita.configure do |config|
+  config.robot.name = 'Lita'
+  config.robot.mention_name = 'lita'
+
+  config.robot.adapter = :gitter
+
+  config.adapters.gitter.token   = 'LpMMyGbceCbUNl4ldRHfzjzb9a48F5WZYbgtBWoi'
+  config.adapters.gitter.room_id = 'Q5cjBQ9BwrNdK0JcicI9AYbL'
+end
+```