The easiest place to start is with the people you already have on your list. Even though they may not be interested in purchasing your services and products, they were interested enough in your business to sign up and show some type of support. You can use your list of current subscribers to generate more subscribers who are more interested in actually purchasing your products or services.
It makes sense: the people who visit your blog post or web page are looking for something specific, so your CTA needs to meet those unique needs. For instance, if you’ve got a ton of traffic visiting your “List-Building Strategy” blog article, why not entice those people to subscribe to your email list by including a simple CTA like this: “Click here to download a free list-building toolkit.”
I always pause and laugh when I see a CTA with a small, “No thanks, I don’t want to lose weight,” button underneath a prominent “Yes, sign me up!” link. It reminds me there’s a person behind the button, and, while it’s meant to be a joke, it also incentivizes me to hesitate before clicking “no, thanks”. It’s easy to click “no” when the CTA is “sign up for more emails!”, but it’s a little harder to say no to losing weight or getting richer.
For effective and actionable results, you should do A/B tests, which test two (or more) different approaches. For example, you could send half of your list one subject line, and an alternate subject line to the other half. You could also A/B test the two approaches with a small subset of your list, then send the winning headline to the rest of the list.