Update the README section 'How to create a new rule' (#267)

README.md

@@ -228,12 +228,39 @@ If it is time to release, @Gillespie59 will bump the version in `package.json`,
 
 ## How to create a new rule
 
-Here are the things you should do before sending a Pull Request with a new Rule :
+We appreciate contributions and the following notes will help you before you send a Pull Request.
 
-- Create a JavaScript file for the new rule in the rules directory
-- Create an unit test for this rule in the test directory (with the same name)
-- Update the main index.js file, in order to add the new rule in the 'rules' property, and set the default configuration in the rulesConfig property
-- Update the "Rules" part of the README.md file with a small description of the rule and its default configuration. In this file, you have to add your rule in the default JSON configuration object. 
+### Check the issues
+
+Have a look at the existing issues, they may exist similar issues with useful information.
+
+### Files you have to create
+
+* `rules/<your-rule>.js`
+    * JavaScript file with the new rule
+    * The filename `<your-rule>` is exactly the usage name in eslint configs `angular/<your-rule>`
+    * Have a look at the `angularRule` wrapper and the `utils` (both in `rules/utils/`) - they probably make things easier for you
+    * Add a documentation comment to generate a markdown documentation with the `gulp docs` task
+* `test/<your-rule>.js`
+    * Write some tests and execute them with `gulp test`
+    * Have a look at the coverage reports `coverage/lcov-report/index.html`
+* `examples/<your-rule>.js`
+    * Add some examples for the documentation
+    * Run the `gulp docs` task to test the examples and update the markdown documentation
+* `docs/<your-rule>.js`
+    * Generated by the `gulp docs` task
+
+### Files you have to touch
+
+* `index.js`
+   * Add your rule `rulesConfiguration.addRule('<your-rule>', [0, {someConfig: 'someValue'])`
+
+### Before you open your PR
+
+* Check that the `gulp` is working
+* Commit generated changes the README.md and the documentation markdown
+
+### Rules specific for Angular 1 or 2
 
 We can use a property, defined in the ESLint configuration file, in order to know which version is used : Angular 1 or Angular 2. based on this property, you can create rules for each version.