I was interviewing for my current job while living several states away and was fortunate enough to have the option to do it over video conferencing (iMeet specifically), saving travel costs for me and allowing me to secure employment before an already-planned move. In addition to the tips already listed I'd add these three:
1) Demo the Tech Ahead of Time - I can't stress this enough. Sign up for a free trial of whatever video service you're using for the interview or at least get in and fill out your profile information to make sure your browser capability and everything checks out, rather than finding that out when the interview is supposed to be starting.
2) Show Up Early - Similar to the above note, but even when your tech checks out, at least be on time, if not a few minutes early. You wouldn't come running into an in-person five minutes late (hopefully!)
3) Be mindful of your surroundings - Even the sharpest professional apperance loses something if the background is a dirty apartment. Find a clean wall or something to set up in front of - make sure you stay the star of the show.
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