Make sure they are parallel, not turned out. Keep both feet active, toes spreading. Imagine you have toes in your heels, and spread them, too.
Place your hands in the strap, palms facing each other, and extend your arms above your head. Lift your head, gently drawing your arms backwards. Don’t hike your shoulders.
Press your lifted leg into the strap and away from your body. Gently move the femur of your raised leg to the back of your thigh so that you feel space in the groin. You can then draw that leg as close as possible to your core as long as you maintain the space you’ve created in the groin.
Keep the thigh on the ground moving downward (grounding your femur) and press that foot into a wall, real or imaginary.