FORTUNE — Now that Microsoft (MSFT) is shelling out $8.5 billion to buy Skype, the

service — which already claims 170 million users and 40% annual growth — seems poised to become even more ubiquitous in the business world.

Already, says Bill Rosenthal, Skype interviews are fast replacing phone screenings as a way for employers to check out job candidates before, or even instead of, an in-person sit-down.

Rosenthal is chief executive of Communispond, a 42-year-old coaching firm that teaches communications skills to executives. His six tips for projecting the right persona in cyberspace:

1. Choose a professional username. As with an email address you use for business, a Skype account with a moniker like hotpants33 or partyanimal2011 is a dumb idea.

2. Practice talking to your computer. Before a Skype meeting or interview, “make sure you’re familiar with the technology,” Rosenthal suggests. “Practice using it. Rehearse with a friend.”

3. Arrange the right setting. You want to be seen against an uncluttered background with no distracting objects, movement, or sound. “There shouldn’t be light behind you, because it will darken your face,” Rosenthal says. “Move your monitor if you have to.”

4. Block out interruptions. Turn off your cell phone, of course, but also, if you’re Skype-ing from home, banish your family and pets for the duration. As with an old-school phone interview, howling dogs and importuning children will do you no favors.

5. Back it up a little. “Don’t move too close to the monitor. You don’t want only your face showing,” Rosenthal says.

6. Make (virtual) eye contact. Gazing at the computer screen instead of the camera while you’re talking will make you seem shifty. But “don’t stare unblinkingly at the camera”, either, which will just make you look weird.

“As in a live meeting or interview, remember that the first impression you make will be lasting,” Rosenthal notes. So, particularly for a job interview, be sure to look the part: “Even if the company has a reputation for being laid-back and casual, wear a suit.” Some things never change.

Editor’s note: A previous version of this story incorrectly stated that Communispond is a 32-year old company. The company is 42 years old.