Start on your hands and knees with a neutral back position (if you don’t know how to set that up, learning that is your first step). Slowly rock back, attempting to pull yourself into position (the active psoas part). Move in and out of whatever pain free range you have (avoid painful movement or pinching). Adding band distraction backwards on the affected side is a great idea.

Generic prescription: 3×15

If nothing else, it will just start teaching you how to feel and contain movement in your hips, so you understand the current limits of your ROM. At best it will help integrate normal femoral head position back into your hip flexion (a start, at least).