hi. sorry for my bad english.....
1- till the bar dont pass the kness only push with your legs in slow motion style, and your torax has to mantain the same angle with the ground.
2- in the moment that the bar pass the kness you do the explosive motion, you finish to push with your legs (ankle full extension also) and you pull with your torax (full pull, also trapezious), i say TORAX, NOT HANDS. Hands are only a guide for the bar, but hands NEVER PULL.
3- elbows high for receptioning the bar, the higher the best, and then.... faster down the bar.
if you dont do point 1, you will never learn how to do 2 and 3, because you cant do 2 and 3 properly.