How you express yourself affects how you are perceived.
The need for this skill is obviously reduced in these days where everyone is working remotely. Furthermore, many people don’t even use video when they are collaborating via Slack and other tools. Still, it is an important skill. And someday, eventually, you will likely have conversations in person again.
When you have interactions in person, or even via video, it is crucial to portray yourself with an air of confidence. There are many nonverbal cues that people will pick up when they watch you. This include how you stand or sit. Try to maintain excellent posture.
Also be very aware of your gestures. If you have none you may be perceived as limp or tired. On the other hand, if your hands are all over the place, you will appear unfocused and easily confused.
It is hard to monitor your bearing because you usually can’t see yourself. It can help to record yourself and study your own movements from a different angle. It also helps to have a friend who can give an honest analysis. Either way, making improvements to your bearing will benefit you down the road.