The way a approached this was to start working on the lip sync first and then, while listening to the audio, figure out the facial expressions and the language of the body of the character. I was very fortuned by choosing this audio, because a lot of the sounds and mimics were very similar through- out the audio so all I needed to do was to create a few and then just narrow down where the sounds were and copy them just before.
After I was finished with the lip sync, I started working on the body movement and the facial expressions. I tried to keep it fairlly simple and not to go overboard with it, because it's not suppose to distract the viewer to much, but at the same time keep it interesting and of course the animation had to be in keept with the actual audio file for it to work properlly.