What's the No. 1 reason people open e-mails? Because they know and trust the sender.

That was a key message conveyed by Suzanne Norman, the director of community relations at Emma, a Nashville, Tenn.-based company that helps clients create, send and track customized e-mail newsletters, during the presentation "Make Your Emails Smile: Design Strategies for Emails in the Inbox and on the BlackBerry" at the Email Evolution Conference in San Diego earlier this week.

“Design and trust go hand in hand,” Norman said. “If you use design to create trust, you can build it and sustain it for the lifetime of anyone on your e-mail list.”

So, how can you use design to create trust? Norman offered the following tips:

1. Make the most of your preview pane. The preview pane -- or the window in an e-mail client that lets the user preview an e-mail message without actually clicking or opening it -- can be a great branding tool, Norman said, suggesting you ensure your brand is prominent there. “Brand your alt text [which is a function in e-mail design that allows alternative text to appear when an image can't be displayed], and give your logo prime real estate," she said.

2. Be stylish. Use crisp images and a breezy, easy-to-understand style in your writing. “When readers see great-looking images, they think 'great brand,'” Norman said, adding that recipients also do not associate great-looking content with spammers. “Spammers do not usually use these techniques, so [recipients] automatically will not think of your e-mail messages as spam.” Norman also said that companies should always think of their e-mail campaigns as an extension of consumers' brand experience with them. “Do a side-by-side comparison between your best print piece and your best e-mail campaign, and see if they are offering the same brand message,” she said.

3. Think of your recipients as individual people. “Find ways to use design to incorporate personal elements into your e-mail messages,” Norman said. “When recipients know that something is coming to them specifically, they have a better connection to the brand.” She recommended adding layers of personalization in the greeting and content, as well as in the feel and the timing of the messages.