Below are pages scanned from Richard Williams' 'The Animator's Survival Kit', by far the most useful and informative book I've ever owned. These pages are my main sounce of reference for the principles of animation I most want to focus on improving in my work. First one: flexibility. Vital for ensuring my character isn't as stiff as an ironing board.
Takes and Accents
Surprise Anticipation - My poor character's going to be shocked a lot.
Weight and Follow Through
Whips and Waves - Especially useful for animating flowing hair.