 So the first thing that you want to do is collect a list of email sources The list of email sources will include things like office 365 of course because that's where your email is hosted But it may also include things like email marketing services. So if you're using things like Mailchamp or constant contact We would need to collect information about where those you know emails are being sent or how those emails are being sent Specifically, we would have to get something called an include from those sources. So if we went and looked online for The Mailchamp SPF include for example, we would get a portion of the record that we would need to add to our own SPF record It would also include things like CRM services or are you using Salesforce or Dynamics things like that. We would need those sources if you send emails from your own website So if you have an SMTP service on your own website that sends email directly from your web server Then you wouldn't need to include the IP address of where your web server is hosted And basically anything else that is sending email as your domain We need to collect all of the information about those things so that we know Where email legitimate email is being sent from as your domain