Take a wide stand with your feet. Hips and shoulder square, back neutral.
Squat to one side, by flexing that knee and hinging at the hips.
The heel stays down throughout, keep your torso upright, and assisting leg straight.
Descend as low as you feel comfortable, staying tight, and not going into posterior pelvic tilt (Don’t let your pelvis tuck under)
Stay low, maintaining a good posture, drive through the heel as you extend one knee, while flexing the other - transition your weight to the other leg.
Repeat for repetitions, and then drive through the heel, extending the knee and hip to return to the start.
Good drill for hip mobility - Make sure to keep your back neutral, and stay upright.