Here are a few ways to encourage people to opt-in to your email list.
Events -- Use free events as a magnet to establish your expertise and build trust to get sign ups.
Guest Posting — Create posts that you share on other sites
Interview People -- The key is to interview people with larger audiences and they will help draw attention to your site
Offer Free Content -- Create guides, ebooks, infographics or courses that will help solve just one problem
Create Incentives — Give away eguides, ebooks, ecourses - pull from existing content; share your expertise
Consistently Blog on your Website (I need to learn to practice the consistently part, myself.)
Promote Other People’s Content Socially -- Promoting other people’s content increases your brand awareness and increases engagement; 80% of what you share should be other people’s content to create a sense of community
Create Partnerships & Collaborations — Collaborate with others to share about your information and events and vice versa. Helping each other will expand your audience and brand awareness.
Build Up One Social Media Channel —Determine where your target audience hangs out. Don’t try to master all social media outlets.
Record Videos & Webinars — Position yourself or your company as a thought-leader by offering free, non-sales pitch webinars. Encourage sign ups to your newsletter, blog or free materials on the videos.
Reach Out to People Socially — Invite people to follow your updates on a specific place, perhaps your website, blog, etc.
Share with Your Personal Network — Friends can be very supportive. Share your content with them and ask them to share your information with others.
If you think strategically about what you can do to get people to sign up, you'll tap into a goldmine. Test the waters to see what works and what doesn’t work. Then make necessary tweaks, as needed.