Recording your audition can be as simple as taking a video on your phone, or as complex as using a recording studio/device/computer. Whatever the case, the most important thing is that your playing/singing is easily discernible. Also, make sure the quality of the recording is acceptable (again, it should be easy to hear what you’re playing/singing). You may need to do several “takes” to get a good recording/balance. Below is an example of an acceptable audition video.