Authentication — proving the email is from you.
Three records on your DNS. They tell Gmail, Outlook, and the others that the email actually came from your domain — not from someone pretending to be you.
Mail servers default to suspicious. If they can’t verify who sent the email, they assume the worst and route it to spam. Three DNS records change that.
Lists every server allowed to send email on behalf of your domain. Without it, anyone can spoof you and the receiving server has no way to disagree.
v=spf1 include:_spf.blueyemail.com ~all
A cryptographic signature on every email proving it wasn't modified in transit and was actually sent by an authorised server.
bluey._domainkey.yourdomain.com → (long key string)
Tells receivers what to do when SPF or DKIM fails — quarantine it, reject it, or just report it. Also gets you the daily report from Gmail telling you who's spoofing you.
v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com
Warming up a domain — go slow before you go fast.
A brand-new sending domain has zero reputation. Send 50,000 emails on day one and Gmail will assume you bought a list. They throttle. You go to spam.
Reputation builds with engagement, not volume. Open rates, clicks, low complaints, low bounces — Gmail and Outlook watch these and decide whether you’re worth showing in the primary tab.
A reasonable warmup ramps over two to four weeks. Day one: send to your 500 most-engaged contacts. Day three: 1,500. Day seven: 5,000. Add a digit when open rates stay above 25%.
Why some emails land in Promotions.
The Promotions tab isn't punishment. Gmail puts emails there when the content reads like marketing — images, big buttons, discount codes, sales language.
Three things move you back to Primary: ratio of text to images (more text helps), use of personalisation (real first names beat generic), and replies (any reply to the sender is a strong signal it’s wanted).
Avoid the obvious traps — multiple exclamation marks, all-caps subject lines, “FREE” in the subject, more than three links to the same domain, an image with no alt text.
Watching reputation — daily, not yearly.
Reputation drifts. A bad campaign last month, a complaint rate creeping up — small things compound. The fix is to look at the dashboard every week, not when something breaks.
Three numbers tell you most of what you need: bounce rate (under 2%), complaint rate (under 0.1%), and the per-provider inbox placement (over 95% for Gmail and Outlook is healthy).
When any of those start drifting, the cheapest fix is to send less, not more — pause low-engagement segments and re-engage the openers. Volume to people who don’t open hurts everyone you do reach.
When things go wrong — a short triage.
The most common breakdown isn't sudden — it's a slow drift. Here's the order to check things in when you notice.
- Check DKIM is still aligned. A registrar sometimes wipes records during DNS edits. Run the verify button in Bluey’s deliverability tab.
- Check the complaint rate. Over 0.1% triggers throttling fast. Pause campaigns to dormant segments and only send to recent openers for two weeks.
- Check sender reputation at Google Postmaster. If you’re on a high-volume domain, register at postmaster.google.com and watch the daily score.
- Re-engage before culling. Send a re-engagement campaign to silent contacts. Anyone who opens stays. Anyone who doesn’t gets archived.
- If a list got compromised, rotate the API key and audit recent campaigns in the audit log. Bluey keeps a full action trail.