Many domain names come with free email forwarding, but sending so it appears to come from that domain name often requires a paid SMTP service that might cost £10/year. While searching I found Pobox that lets you set up multiple domains for a flat fee, which had the bonus of working via email forwarding that would let me keep my mail in Gmail.
Set up a email forwarder on your domain name, to ensure that any emails get forwarded you your Gmail. Verify that this is working as it’ll be used by Google to verify you own the domain.
Consider using an alternative service if your domain registrar will aggressively block emails with attachments as spam.
Create an app password as if you were setting up a mail app on your phone or computer.
Set up 2FA first to get that option.
Add a new email address from your Gmail account settings. Set your chosen email@example.com as the email address, and untick ‘treat as an alias’.
Configure Gmail to send with:
- SMTP Server: smtp.gmail.com
- Username: firstname.lastname@example.org address
- Password: the new app password set up above in Step 1
- Port 587 over TLS
Confirm and you’re done!