The subject line’s job isn’t to sell, it’s to get the email opened.
The subject line’s objective is to not get the email deleted when it’s read quickly by your prospect while walking between meetings.
The subject line is your one-story elevator pitch. What will you say to get the prospect, when the elevator door opens, to say back to you “interesting, walk with me and tell me more…”
The colder your relationship with the prospect, the shorter your email should be.
If you’re 100% cold, assume your prospect will delete your email vs scroll beyond a single screen on mobile.
They won’t trust your attachments yet so don’t send them.
Don’t make the prospect do work (that includes asking them to “direct you to the right person”)
Say “you” more often vs “we” and “I”, especially at the beginning of a sentence.
Read your copy out loud before you send it. If it sounds awkward, it is