One of the most common questions we get at my email marketing company, VerticalResponse, is: "How can I make sure my emails look good on cell phones?"

Cell phones have come a long, long way from the massive, cumbersome bricks they used to be. More than one-third of Americans who own cell phones use them to go online--you might be reading this article on your mobile right now--and more than half of Americans check their email inboxes on their phones, according to the Pew Research Center.

The good news is that because people are checking their emails more often, they're more likely to see your e-newsletters, promotions, and invites.

The bad news? An email designed to be read on a desktop or laptop computer could look downright horrible on a smartphone, which means your recipients might just hit Delete before reading your message.

So let's get to it. Here's a quick cheat sheet on how to make sure the emails you send for your business look great on mobile devices:

1. Go easy on images.

"Clean and simple" are key when it comes to mobile-optimized emails. Don't overdesign with too many images or embed large image files, because they might take forever to load on phones that rely on iffy Wi-Fi connections.

2. Use a responsive template.

If you're using a predesigned template from your email service provider, make sure it's responsive. Responsive email templates are designed to automatically fit the screen on which they're being viewed, so your email will look the way it should whether on a smartphone, tablet, or a PC. If you use a responsive template, you don't have to worry about your email rendering incorrectly.

3. Be word-wise.

Pay close attention to your "from" label, subject line, and preheader text. You've got such small real estate to grab attention, so make every word and character count. For example, an iPhone displays only the first 30 or so characters of a subject line when the device is held vertically, and the "from" label is actually displayed more prominently than the subject line.

4. Break up text.

Avoid long paragraphs, and don't crowd too many links together at once. Put the most relevant and important information first. Because your readers are probably on the go, they might be easily distracted if you don't get to the point right away.

5. Befriend buttons.

Use buttons for calls to action instead of links. Buttons are easier for people to click on when using a touchscreen (which most smartphones have these days). Leave plenty of space around your buttons to avoid a "fat finger" mishap. Here's a handy, free button-builder tool.

One final thought: Make sure the links you have in your email direct readers to a mobile-friendly webpage. There's perhaps nothing more frustrating for an on-the-go reader to click off an email to a page that doesn't render correctly on a smartphone. Check out this post, "How to Optimize Your Business Website for the Mobile Era," for some helpful tips.

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