This is a great exercise to help lengthen your hip flexors and regain better pelvic posture.
Start in a half-kneeling position with your right foot forward and your left knee down. Spread your toes on the right foot for better balance. Curl your toes under on the left foot and take both hands and place them on your hips or a chair/counter for balance. Tilt your pelvis under and breathe deeply to reduce tension and tone. Try to stay tall throughout the exercise. Hold for 1-2 minutes on each side.