Add pull request submission instructions

README

@@ -10,4 +10,8 @@ This project demonstrates collaborative development using Git and GitHub's fork-
 2. Create a feature branch.
 3. Make your changes.
 4. Commit and push your changes.
-5. Create a pull request.
+5. Create a pull request.
+
+## Submitting a Pull Request
+
+To contribute changes, create a feature branch, make your changes, commit them, and push the branch to GitHub. Then create a pull request so the changes can be reviewed before they are merged.