Transforms Into A Guitar explains where you should (and shouldn't) put your music stand. You DO have a music stand, right?
I thought the posture series was finished but as I was editing this I realised it fits on the end.
This is based on Michael Bonner's PhD research on the ergonomics and physiology of playing classical guitar, which focuses on the prevention of performance-related musculoskeletal injury.
https://youtu.be/AfmoTXkwOzg