The Joe Pass Method

 

    In order to gauge the ability and creativity of new students, Joe Pass would make his pupil improvise over a given chord progression using only eighth notes.  This may sound strange or "non-musical" to you, but it's a good way to assess your creative abilities by forcing you to rely on your brain rather than licks or cliches you've memorized.

    This is also a great exercise for practicing improvisation.  By limiting yourself to a single note value to improvise with, it forces you to focus on the shape and contour of your lines as well as how convincingly you are connecting the chord changes.  It may sound counterintuitive, but forcing this kind of limitation on yourself while practicing can actually help with creativity.  

    Developing a solid linear approach to improvising on your instrument is essential for creating tasteful, singable melodies.