Placement of the camera is one of the biggest factors in producing a good-looking and useful video. It’s most important that the viewer can see the student’s hands and the keyboard, although it’s also nice to see who it is that’s playing (body and face!). It’s not necessary to keep the entire student body and piano in the frame.
The best position is standing (or mounted to a tripod) to one side of the student looking over their shoulder. Sometimes if you ’re too close the sound may be distorted. If so, either adjust the volume (on digital pianos and keyboards) or move the camera further away until the sound improves. Then, zoom in to recreate the recommended framing. Also, you may want to use this approach to avoid the camera being so close to the performer that it’s distracting for them. Note, though, that the further you are away from the instrument, the more reverberant sound you will pick up from the room.
Once you ’ve found your best location, simply hit record and keep the camera as still as possible. Zooms and pans while recording are unnecessary.
If you are using a smartphone, make sure you have it in landscape mode, i.e. horizontal.