1. Your subject line is a pre-promise, not a hook:
The goal isn't to trick someone into opening
It's to set an accurate expectation of what's inside and attract the right opens from the right people
A 20% open rate from people who wanted what was inside will always outperform a 40% open rate from people who opened out of curiosity and immediately deleted it
2. Your sender name matters more than your subject line:
Before anyone reads your subject line, they read your sender name.
That name activates whatever association they've already built with you.
If you've been coded as useful, they lean in before reading a word. If you've been coded as noise, even a brilliant subject line is fighting uphill.
Be consistent. Make it human where possible.
3. Write subject lines and preheaders as one unit:
The subject line opens the thought and the preheader completes it.
If they say the same thing twice, that's wasted space.
If they contradict each other, that's confusion.
Write them together, always.
What also works:
→ Audience language: use the exact phrases your audience uses to describe their own problem.
→ Specificity - concrete detail signals real substance. "How to add 200 engaged subscribers a month" beats "grow your email list" every time
→ Open loops - curiosity that the email actually satisfies. Open a loop, close it. Don't manufacture mystery around ordinary content
→ Questions your subscriber has already asked themselves - direct address of something real in their world
→ Clarity over cleverness - be clear about what's inside. The people who open will be interested.