Improvising on a Melody
To get started, we need a melody to work with that everybody has down cold. How about that one about Mary and her little lamb? And let’s put a Jimmy Reed shuffle rhythm behind it to move it from the schoolhouse to the local nightclub and give us something to work with (Example 1).
Review the melody a couple of times. Find it in more than one place on your guitar neck (Examples 2a–c). Usually when musicians think about improvising on a melody their first thought is something like, “I need to come up with a variation on the melody notes.” Think about this, however: music is said to have three elements—melody, harmony, and rhythm. All these elements are fair game for improvising, not just the melody notes.
Excerpted from Acoustic Blues Guitar Basics