Kneel on one knee with the other foot planted in front, both knees bent close to 90 degrees. Keep your torso upright, brace your stomach lightly, and tuck your pelvis under by squeezing the glute of your kneeling-side leg — that shifts the stretch from your hip crease into the front of that hip and thigh. Avoid arching your lower back to reach deeper; that just borrows range from your spine and hides how far your hip actually moves. A small forward shift of your hips, not your chest, adds depth. Pad your kneeling knee if the floor makes it hard to relax into the position.