The 2014 National Retail Federation (NRF) Convention, held January 12-15 in New York City, showcased some of the brightest innovations in retail technology. However, research shows that new strategies like social media advertising and mobile apps are no replacement for some of the classic tools of the trade. Just as the importance of customer service will never die, email is likely to remain a winning strategy for years to come.

According to a recent McKinsey & Company report, email marketing is nearly 40 times more effective for customer conversion than Facebook and Twitter combined. Despite the gains made by Facebook messaging services, email remains the primary means of electronic communication, which means that it's generally the most reliable way to reach customers.

Of course, merely getting a message to an inbox is not enough. There are a few best practices that retailers can follow to make sure their emails have a greater impact.

1. Always be useful. Justin WIlliams, a marketing strategist for StrongView, reminded retailers that usefulness is the key to having customers open emails time and again. Whether merchants are sending email receipts or deals, they should use retail customer intelligence to personalize the message and options.
2. Give subscribers options. Williams and McKinsey & Company agree that bombarding customers with emails can be counterproductive. Regular contact is a good thing, but not when it's unsolicited or annoying. Letting individuals choose which types of emails they want to receive or how often they want to see deals can help retailers foster positive engagement. Merchants should make it easy for customers to unsubscribe and resubscribe so they don't feel like they're being spammed.
3. The click is not the goal. McKinsey & Company suggested that customized landing pages, rather than links to generic home pages, are far more effective because they're more useful for customers and they draw people deeper into the shopping journey.
4. Plan for mobile. As individuals increasingly read email on mobile devices, email marketing strategies must incorporate designs that are optimal for the platform. That includes designing buttons and links that are easy to select with fingers rather than a mouse.
5. Be trustworthy. The need for secure links and ecommerce software is a no-brainer, but retailers must also make sure their emails are reassuring and dependable. Williams recommended keeping language, style and images consistent so customers know what to expect. This also helps consumers recognize emails that falsely claim to represent a company.