We covered so far almost all these aspects, but here are some more tips to create successful CTA:

• so, if you want your visitors to do something, just tell them so
• if you don’t do that, they will just like your content and move on, simple as that
• You can use authoritative words (now, today, click here, go there, use, subscribe...) or just proposals (if you want to ..., I propose to ...., my suggestion is ..)
• I recommend to use more imperative and command words or phrases, because if you tell them that they can come back anytime and “enroll anytime”, instead now, it will happen very rarely that they will come back and enroll.
• The competition is too big and they might “fly away” and look for another option, unless your content is so valuable they can’t allow themselves not to come back and subscribe to your service or even to buy your offer, but, believe me, it happens really rarely
• Be sure that just posting CTA is not going to be enough to achieve massive results. There are other things you have to do properly, but CTA is unavoidable part of it
• Depending on your content and the purpose of it, you should include CTA at least, minimum one time, best at the end of the article (although some online marketers are placing CTA already at the beginning of an article or post), or even more times on more places throughout the content. Test it out.