Correct indentation is very important for YAML data. It's recommended to use an advanced text editor such as, Sublime Text or Notepad++, as they have options that convert the tabs to a specific number of whitespaces. At the same time, you can choose the specific tab indentation size to be 2 or 4. So, your editor will convert the tab to a static number of whitespaces whenever you click on the Tab button. Finally, you can choose to display vertical lines at each indentation to ensure that lines are indented the same amount.
Please note that Microsoft Windows Notepad doesn't have that option and this may result in a formatting error in your YAML file.
The following is an example of an advanced editor called Sublime Text that ...
