Really struggling to get this down, it's most famously done in School Days by Stanley Clarke. But also in the beginning of 'U Can't Hold No Groove' by Victor Wooten.
I can get a sound out, but not a nice consistent one like how it's meant to be. The motion seems to be from the arm, wrist and fingers all at once. Very weird.
Any tips on that?
Example:
http://www.youtube.com/watch?v=gl-CxMiW-1Y