The actual validation process can be launched from either the actual data (a card page or a list page for example) or from the validation templates themselves.

The Validate Data icon can be found in the Actions tab of the Ribbon on the Customers List page, for example.

NB: If you run the validation from a list page, you must select multiple records, otherwise only the record selected will be checked for validation

In the example below the Validate Data button is also on the Customer card page, in the Actions tab of the ribbon.

The Validate Data is also available from the Actions tab in of the Ribbon on the Validation Templates List and on each of the individual templates.