oh my gooness, what a beautiful boy! He looks like he could be a pretty powerful ride and you have a nice, quiet look about you.
You need to open your shoulders more. It helps me to think about trying to touch my shoulder blades together.
Also, you are jumping ahead. Your butt should be back more, over the center of the saddle. Someone above commented about your legs and gaining a more solid foundation/position in your legs will definitely help. Another thing that I do that worked wonders was counting before the jump. Anywhere from like 5-7 strides before the jump I start counting 1-2-1-2-1-2, one number per stride. It helped me a lot to get my focus off the fact that we were going into a jump and and more on the counting. Because of that, I was waiting with my body and therefore not jumping ahead.
Hope it helps! :]
~live. laugh. ride.~