To do the gestures you see in the video? I learned that watching Lang Lang playing on his "Live in Carnegie Hall"
I can play professionally by sitting still and all those things they teach you at university. Yet, playing like Lang Lang plays helps reduce nervousness, and that's another topic on gestures in performance.
back to the topic
To play the agitato in Ballade no2, take it slowly applying the "right" technique and fingering.
yeah, and it obviously works very well. The tone quality and the speed is amaaazing! It almost lives up to a grade 2 standard! In a few years, you can probably compete with a simplified Marry had a little lamb.
As Dan so geniously pointed out, you need to use both right technique and fingering. To use the wrong technique, like playing with with your toes, will probably not take this coda to perfection.
First of all, play only the melody. Think of how you want to phrase it. As Leon Fleisher to cleverly pointed out: "Technique is to be able to make the music sound like you want it to".
If you don't know how you want it to sound, playing fast notes wont take you anywhere, cause you will have to start over anyway. So always think of how you want it to sound - where does the phrase go, and where to emphasize... Maybe you will realize that you actually like it a bit slower than what you first thought.
The technique itself is like the Chopin studies: We can't really tell you, because everyone uses different techniques, and what works for one might be even physically bad for an other.
To not sound like an important teacher, who has no technique, but only very deep words:
My wrist goes up and down, and very much into the keys, when I play it. And in the chormatic part, I sort of "stiffen" the wrist in a very high position, and shake it from the arm.
One of our lovely experts, who's name I can't spell, might say "You are wrong.. blah blah, however, I'm right.. blah blah...". That's very much his right to do so, but his perfect technique might not work for everyone.
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Edit: Maybe I wrote this already, but I felt that I can't Only write bad things about some users here without giving some sort of feedback...
Edit no 2: Sorry, I didn't notice you already came up with a good way of playing it..
Congratulations!

If you still have problems with the leaps, you need to take the time to look where you put your fingers. Just a very quick look at both sides, so you see where the notes are, and then wee where you hit the wrong ones. And then look more on the side where you tend to miss..