Add requirements creation workflow and big changes guidance to contribute.md

contribute.md

@@ -14,11 +14,35 @@ To contribute code you need to issue a Pull Request. All code submissions will b
 
 You must sign a [Contribution License Agreement](https://cla.microsoft.com/) ([CLA](https://cla.microsoft.com/)) before submitting a Pull Request. To complete the CLA, you will need to submit the request via the form and then electronically sign the CLA when you receive the email containing the link to the document.
 
+## Big contributions
+If your contribution is significantly big it is better to first check with the project developers in order to make sure the change aligns with the long term plans. This can be done simply by submitting a question via the GitHub Issues section.
+
 ## Things to keep in mind when contributing
 Some guidance for when you make a contribution:
 
-* Add/update visio diagram when required by your change
+* Add/update the Visio design diagram when required by your change
 * Add/update module requirements as required by your change
 * Add/update unit tests and code as required by your change
 * Make sure you run all the unit tests on the affected platform(s). If the change is in common code, generally running on one platform would be acceptable
 * Run end-to-end tests or simple sample code to make sure the lib works in an end-to-end scenario.
+
+## Editing module requirements
+We write detailed module requirements that we trace in the code and unit tests. In order for each small requirement to be traceable it receives an Id. The requirement Id is generated by using a Word macro that is embedded in the requirement document.
+
+The below steps describe adding a new requirement:
+
+* Add the requirement text and select it
+
+![](media/add_requirement/add_requirement_step1.png)
+
+* Invoke the macro with the selected text
+
+![](media/add_requirement/add_requirement_step2.png)
+
+* Select developer id 99
+
+![](media/add_requirement/add_requirement_step3.png)
+
+* Done!
+
+![](media/add_requirement/add_requirement_step4.png)