Verify the custom field appears the way you want it to
When creating a custom field from a saved transaction or other supported record in view mode, or from the Customization section Fields page, you can test how the field works to ensure it displays the way you want it to. You can then make any necessary changes before committing to the final step of creating the field. You can also test the field in the Preview section.
For more information, see Create a custom field.