Discus

Discus was originated and Greece and was watched to look at the athletes coordination, grace, and physical strength while throwing. It started off just for men and the weight depended on whether you were a boy or a man. The typical discus weighed around 13 lbs. Women didn't throw the discus in the Olympics till 1928.
Today, boys in high school throw a disc that is about 1.5 kg and girls throw 1 kg. Depending on a mans age, the discus will vary in weight while for women it will stay 1 kg. You are constricted
to a circle that is 8 ft 2 in. in diameter. While throwing, you start off facing the opposite way you throw. You then turn counter-clockwise (for right hand people) and do one and a half turns before releasing your throw. While releasing your throw, you want to keep your head pointing up as in looking at the sky and your arm being the last body part to come forward. You want to snap your hips to get the greatest strength and motion for the best throw possible.
You have a total of three throws, each will not be measured though. They keep markers in the vector and if you throw shorter the second time they will not be moving your marker, unless your throw goes farther. Your throw is measured from the spot your discus first hits the ground and goes to the front edge of the circle.
What can you do to make sure your arm stays back before you release the discus for the full snap with your head up high?