A communications coach explains how to make sure people get what you're trying to say, even if they're also checking their BlackBerrys.

By Anne Fisher, contributor

FORTUNE -- What with teleconferencing, Skype, and global conference calls, technology has wrought a sea change in the way people hold meetings. That can be great, not least because it saves some big companies millions annually in travel costs. The downside: Coming across effectively in a virtual gathering is tricky.

"Most executives today 'grew up' with in-person meetings where everyone was seated around a table in the same room," says Scott Weiss, CEO of communication consulting firm Speakeasy. "So a virtual meeting is a strange environment, partly because you usually don't get immediate feedback to let you know how you did."

Small wonder, then, that although 67% of senior managers in a new Speakeasy poll expect more virtual confabs in 2012, 62% say they're concerned about their own skill at making the most of these meetings.

The risks in blowing it are real, Weiss notes. "Let's say you have a regularly-scheduled quarterly strategy meeting with all of your senior people in various locations, and you decide to do it as a teleconference," he says. "If everyone doesn't get everything that's being said, or someone doesn't have a chance to contribute vital information, you might not realize it until much later -- after substantial damage has been done to the business." Gulp.

Weiss and his team have coached executives at Fortune 500 companies like Coca-Cola (KO), Microsoft (MSFT), Home Depot, UPS (UPS), and General Motors (GM) on how to avoid that. A few pointers:

Minimize visual distractions

Obviously, in a phone meeting this doesn't matter, but in a teleconference where your audience can see you, "dress as you would for a television appearance," Weiss suggests. That means conservative, simple clothing, like a dark suit and solid-color shirt or blouse. Avoid white, since it can create a glare under the lights, and busy patterns like houndstooth. More