Simon Rob wrote:
What is the quickest, best and easiest way of making a self tape: balancing these factors out? Perhaps also what best quality method making would be?

There are a lot of variables involved in these questions, and a lot depends on what is "best" for your situation.

If you are shooting videos for auditions, they just need to see and hear you clearly.  So, you could face an eye-level window with the camera in front of you.  Of course, make sure the exposure isn't too bright nor too dark.  It couldn't hurt to remove any distracting objects or clutter in the background.

In regards to audio, you should have the mic as close as possible.  It can be inside the frame if it is an audition, as long as it doesn't obstruct any part of you that needs to be seen.  If you hold the mic, it might restrict your gesticulation, which is an expression that probably needs to be seen.