Most professionals use email every day for business — in fact, it’d be hard not to, with 281 billion messages sent and received on a daily basis. But when it comes to marketing, much of the attention gets focused on social media, which — while popular and highly visible — has a conversion rate less than half that of email marketing (4.29% vs. 1.81%), according to a recent analysis. Indeed, one 2015 study revealed that email marketing had an average ROI of £38 (about $50 USD) for every dollar invested.

　　With returns like that, the question is clear: How can we build our email lists? I’ll share three strategies I’ve learned in the past four years, as I’ve worked to build my mailing list to nearly 50,000 people. But first, an important note: You should always let subscribers opt in. It’s both a violation of anti-spamming laws and a deep annoyance to your intended audience if you simply add people without their permission (this includes LinkedIn connections or people who have given you their business card). Additionally, if you’ll have subscribers in the European Union, you’ll need to be aware of new GDPR (General Data Protection Regulation) laws; most email marketing companies will offer a primer for their customers, including additional checkboxes and notifications you can trigger for European IP addresses.

　　First, it’s essential to develop a lead magnet — a free giveaway that people can download in exchange for sharing their email address. (Here’s an example of one of mine.) Yes, you could simply have a link to “sign up for my e-newsletter,” and some do. But they’re the exception.

　　Most professionals are so inundated with email newsletters these days, they’re reluctant to sign up for yet another. But if you can offer something that readers will perceive as valuable — an e-book, a link to a sought-after webinar, or access to otherwise-private video interviews, an subscribe to newsletter, for instance — then they’ll likely be willing to at least give your email list a chance.

　　Second, you can ensure that a link to your lead magnet is featured prominently in any content you create, such as in the bio section of blog posts, and that you mention it during podcast interviews. These are extremely simple things to do, but they make a disproportionate difference. For instance, during the launch of my first book, Reinventing You, I didn’t have a lead magnet, and it didn’t occur to me to suggest during interviews that listeners visit my website. My email list grew only marginally.

　　Two years later, while promoting my next book, simply becoming more disciplined about mentioning the opportunity to “download my free, 42-page Stand Out self-assessment workbook” at the end of any podcast interviews enabled me to grow my list by more than 15,000 subscribers in only 10 months. In similar fashion, I began writing less for publications that didn’t allow me to include my lead magnet in the bio section of the article, and prioritized writing for those that did.

　　Third and finally, you can grow your email list via cross-promotions. As I describe in my latest book, Entrepreneurial You, if you have a good relationship with someone and your products and focus area are aligned, entering into a joint venture arrangement can be a great way to introduce each other to your respective audiences, increase the size of your mailing lists, and earn some revenue. Here’s how it works.

　　When I partnered with Dov Gordon, a consultant who runs a listserv for marketers interested in joint ventures, I sent an email to my list promoting a free teleseminar he was conducting about how to improve the marketing process. I explained my connection with him, my respect for his work, and why readers might be interested.

　　When any of my followers registered for his teleseminar, they were added to his email list (which they could choose to unsubscribe from at any point). And if they signed up for his consulting services, I would receive a share of the revenues. The net result? Hundreds of new email subscribers for him, and $3,500 in affiliate commissions for me. The key, of course, is ensuring that you choose your partners wisely, since their content and tactics reflect back on your brand.

　　There’s no shortage of pundits arguing that email is dead, or at least dying, soon to be replaced by Slack, WhatsApp, or some heretofore unknown communication channel. And yet — for better or worse — almost all of us still use email every single day. Letting someone into our inboxes is an act of profound trust in this oversaturated era. By following these strategies, you’re far more likely to earn your place and reap the rewards.