Location
Find a location with little background noise. Avoid areas with lots of echoes.
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Avoid having your light source in back you to eliminate being backlit.
Camera setup
Whether you are using a mobile device, desktop/laptop computer with a webcam, or any type of camera, make sure to check your camera settings and you are capturing one of the following formats: 720p or 1080p.
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Avoid clothing with colors that blend in with your background, accessories that make noise.
Smile
Additional tips
Do a short recording test to make sure you can see and hear yourself clearly.
Begin and end your recording with a brief moment of silence to allow room for any editing that may be needed.