1) In your hang start position, push your knees back until your shins are vertical. Weight on the heels. Shoulders in front of the bar.
2) Push through the heels as you explode open and up (your heels will lift and the pressure will move to the balls of your feet naturally).
3) Push the bar back into your hips with your lats as you extend.
4) be more aggressive securing the bar overhead. Squeeze the shoulder blades together tightly and punch the palms up through the bar.