These are a few tips for the trainer/expert:
If you have a student that need you to be visible, make sure you are in good lighting. Avoid lighting coming from behind, and make sure it is bright enough. Webcams rarely function properly in low light. The background should be neutral as to not disturb the image.
We recommend using the headset, so you and your student can communicate in the best way possible. Headsets used with smartphones typically work fine but make sure the connector fits in the computer/tablet microphone opening before you start the session.