The struggle with conversion copy is that there’s such a fine line between captivating and cliche. Your choice of tone, phrasing or even a single word could be the difference between an irresistible line that converts effortlessly or distasteful clickbait. 

Email subject lines are some of the most difficult to craft. How do we write subject lines that connect with users so deeply they can't help but click? How do we write the kind of copy that stands out in inboxes yet doesn't appear 'spammy'?

This article from Simply Cast helpfully rounds up some of the most common email spam words and phrases, so we can clean up our copy and start writing authentic, honest and irresistible email subject lines. Some of them aren't as obvious as you might think. I've definitely seen a few of these worm their way into my writing before.

Bookmark this list, save it, print it out, pin it up over your desk - whatever you need to do.

And when all else fails - sell the promise, and deliver it!