Shadow boxing tips

Hello everyone, I'll get straight to it!

What exactly is the purpose for shadow boxing? What things am I looking for or working on?

These are things I work on or look for when I do it and I'd like some advice or tips on how to get the most out of shadow boxing.

- Loosen up my arms, shoulders, and body.
- Keep an eye on how I'm throwing my punches I.e. The technique, movement etc.
- Openings on my stance when I throw combos.
- My balance as I box.

I've read on here a while back to imagine you're fighting yourself, and that also helps with my head movement and not staying in one spot.

What works for y'all??