I'm not sure you have time to provide feedback on posture, but I'll try!
Hi, yes, happy to give you some feedback :-)
Your photograph shows you standing in a 'leaning back' position. This is a common postural habit, which puts compression into your lower back. You will find the 'rib anchor' exercise and 'inner corset' invaluable techniques for correcting this. If your lumbar area is deeply swayed (obscured by your elbow), which I suspect it is, stretchsitting and stretchlying, as in Esthers book, are a great place to start to make stacking your torso upright easier.
Your shoulders will also thank you for lots of gentle shoulder rolls to help them migrate back home towards your back rather than your chest.
Immersing yourself in the book and following it chapter by chapter will help educate your eye for where you want to go. You can always reach out to a teacher if you would like more personalised and detailed help. All the best!
Wow, great advice! Thanks Clare!