Nudge people just enough for them to invest time and money for your online course. You need to send emails consistently, with intriguing subject lines that will make them Start 7 Days Trial. For example, social media influencer Deepak Kanakaraju, for his blogging course newsletters, has subject lines like "Myths about blogging and how you should overcome it" and "Three reasons to enroll for the 100-day blogging video course". Who wouldn't want to open these emails?

Once you have their attention, create content that further encourages them to register for the course. Sending consistent emails about the benefits of signing up will feed their curiosity. Address their fears and issues and let them know that your course will serve its purpose. Analyze who would want to subscribe to your online course and target them accordingly.

Personalizing an email will make your audience feel like your course is tailor-made for them. For instance, if you're someone who provides a course for IELTS, an exam that's required to gain admission to many international universities, you can write about the myths around IELTS or an email titled "Tips to prepare for IELTS, for working professionals". In this case, this works because most working professionals find it difficult to prepare for these exams.

Track how people have responded to your emails—if they've opened them, or the attached links and files. You can then retarget the ones who've interacted with your emails, but still haven't signed up for the course. These are good leads and require persuasion in the form of effective follow ups.