Create custom user-defined variables in Google Tag Manager to suit specific requirements that might not already be covered by built-in variables.
To create a new user-defined variable:
- In the left navigation, click Variables.
- In the User-Defined Variables section, click New.
- Click Variable Configuration and select the desired variable type. See the list of variable types for web pages or mobile apps for details.
- Complete the options for the selected variable type.
- Name the variable. Use a naming scheme that is descriptive of the variable's function, e.g. "Data Layer Variable - Product Name."
- Click Save.