Here are some tips for a great video:

1. Have a clear and interesting introduction
2. Add some simple music in the background as ambiance
3. Keep lighting consistent
4. Separate your soundtrack from your video track; most video editing software can do this
5. Add graphics in video editor, but use it only to communicate key points
6. Make sure the video changes its framing every 5-8 seconds; you can do this simply by making the frame zoom in or out a bit; or you can add stock footage
7. Cut out mistakes (e.g. mispronunciations or fillers)
8. If possible, you can use B-rolls
9. Add sound effects, but only if it serves a specific purpose
10. Create a simple outro so the video doesn’t feel like it has ended abruptly

On top of all, experiment! As they say, practice makes perfect!