Keeping the squash and stretch principle in mind, I have created a simplistic character in Adobe Flash which has been animated to jump.
I found that the 'onion skin' tool was particularly helpful as it allowed me to animate the character straight ahead - creating a good level of fluidity. The use of colour also allowed me to control the body's volume throughout the animation. I also played different music and sound effects alongside my animation to experiment with the impact that sound can have. On the other hand, I found it difficult to maintain a consistent line thickness due to Flash's smoothing.
To overcome this I removed all outlines, leaving the character's motion unchanged.