Update CONTRIBUTING.md

Author: cdimascio

CONTRIBUTING.md

@@ -36,6 +36,19 @@ See something that needs fixing? Got an idea for a new feature? Contribute!
 - Create a PR
 - Have fun!
 
+## Create a Pull Request
+
+1. Fork it
+2. Clone it to your local system
+3. Make a new branch
+4. Make your changes
+5. Push it back to your repo
+6. From the Github UI, Click the Compare & pull request button 
+
+   NOTE: this button will be present for some period of time after 5. If the button no longer there, Create pull request and select the branches manually)
+6. From the Github UI, Click Create pull request to open a new pull request
+7. Detailed steps with example here:
+
 ## Project structure
 
 `src` contains the source code