Steve Beardall wrote:
When you say "configure", do you mean create an MX record at my domain registrar that forwards emails to Gmail(Google)? I don't think that would works because Google requires authentication when you relay messages to their SMTP server.
No I don't. Quite often, providers like whoever you've got your website hosted by, provide a number of ways of handling email - either by creating inboxes on their site (which you pays extra for), or provide you with (eg) a dozen email addresses that you can define forwards for to the email host of your choice .. gmail for example.
What I'm suggesting, is that you look at what email features are provided to your by your hosting service .. if you have the 'forward' capability, you just need to automatically forward emails to (your example) firstname.lastname@example.org on to the gmail account of your choosing. Then, in gmail, you define cleanmy.cloud as a legitimate domain from which you can send emails. You then either just use the web gmail client, or set up your account/authenticated smtp logins from your desktop client using your normal gmail login. No MX setups whatsoever.