You can setup [[Postfix]] to send as an Internet Site. And you can even use it to send mail through an external service like GMail (called 'smart hosting'). Once you do, you certainly need to add or reconfigure your domains [[SPF]] record in [[DNS]]
If you're not outsourcing everything through a third party, you'll want to implement [[SPF]] and [[DKIM]] and [[DMARC]]. Even if you're using a third-party like GAFYD, if you've got a [[CiviCRM]] instance managing all your constituent mailing, then you're going to need to setup these anti-spam measures.
== Tools ==