It's time to debunk another email marketing myth: Subscribers who view your email messages on their smartphones will go back and read them again on bigger screens.

That doesn't happen very often, according to an eye-popping statistic I found when compiling data for a recent Email Insider column, "Are You Ready for a Mobile Subscriber Base?"

Only 3.3 percent of email readers view a message on more than one device, according to a Litmus study. That's a much lower percentage than I, and probably you, would have expected.

This means that your email has only one shot at being seen. Given the rise in mobile email viewing, then, it's more important that your email looks good on a smartphone, tablet or high-end feature phone as well as a desktop or laptop computer.

In other words, assume now that you get only one shot at getting your email read, and it had better render correctly and deliver its message on any screen size.

Would your most recent email campaign pass this test?

“Mobile Triage”
"Inbox triage," a concept pioneered by email marketing guru David Daniels, asserts that email readers will use a mobile device to sort their email inboxes, deleting unwanted messages and leaving others to be viewed right then or for later viewing at the office or at home.

That concept is even more accurate now, except marketers must assume that any message that survives the first cut will get viewed only once.

This reinforces the urgency to create messages that will look good at the first viewing, no matter which screen the subscriber uses.

Why “Mobile First” Makes Sense
An email optimized for a mobile screen will render well on any big-screen desktop or laptop computer, even though it might not have as much detail.

The reverse is not true with desktop messages, however, as we’ve seen so many times with messages that require the reader to scroll through page after page of blocked images and rivers of fine print.

Making your messages more mobile-friendly will take a little bit of work up front, but in the end you might find they're actually more reader-friendly after all.

How “Mobile First” Email Works
In a "mobile-first" strategy, your email looks as good on a small screen as it does on your big 21-inch monitor. Most often this means slimming down your original message, size-wise as well as in the amount of content in your message.

Below are two tips that can help you begin to make the move to a mobile-first email program that serves your bigger-screen readers just as well. In future blog posts I'll share more leading-edge design and coding tips from some of the industry's top mobile design experts:

1. Rethink design.
Below is a list of qualities that distinguish a mobile-friendly email from its bulkier desktop counterpart:

• It's scannable. Your reader can get the gist in the first screen without having to scroll down two or three screens to find your call to action or key content.

• It uses larger font sizes. Think "small screen/larger type." Assume your user doesn't h