Quoted:
Shorten draw length a half inch, relax your grip hand (as indicated), both eyes open and keep your finger off that trigger unless you are aiming at a backstop.
Beyond that, it's more about doing the same exact thing every time. This will net you better results than constantly tweaking your form, anchor equipment etc...
I was going to say it looks like your drawlength might be a half inch to an inch too long. A tell-tale is that you're leaning back slightly (you've run out of wingspan, so your body is arcing back to make up the rest). Your spine should be perfectly vertical when you are in your comfortable hold and all anchored up. The bottom of the collar of your shirt should be directly over your belt buckle. And release hand forearm should be running parallel with the arrow, both vertically and horizontally when your draw length / release length / d-loop length is perfect.
Too long a drawlength also makes you creep forward before the shot because your body is hyperextended trying to hold the string all the way back and it will have a tendency to want to relax into your natural (shorter) draw length.
When you have your drawlength right, you will find shooting to be extremely pleasurable. You can hold against the backwall and aim with absolutely no creep.