How do I get the custom fields to be displayed in the emails sent to my customers?

You can insert custom fields in both the subject and body of your Invoice notification template. Click on the Gear icon on the top right corner of your screen and navigate to Email Templates -> Show Mail Content.

You may then use the following placeholders to show custom fields in the respective module’s email templates :

To insert label: %CustomFieldLabel1% , %CustomFieldLabel2% , %CustomFieldLabel3%

To insert value: %CustomFieldValue1% , %CustomFieldValue2% , %CustomFieldValue3%

P.S: If the value of the custom field is empty, it won’t be displayed in the email even if the placeholder is present in the template.