if you consider like I have said before 6 parallel keyboards,every move on one string (along a scale of choice),will have the notes on the other strings playing the scale displaced with respect to that string.Therefore playing a note from the scale along with another one from the scale and another one...will give you a fundamental grasp of harmony.Now locate Twinkle Twinkle Little Star and form variations of this melody by including one note from another string along with the main melody.This needs for you to plot the scale lol...so if you do not remember the scale do it to make the nursery rhyme come to life,then slap and pop the strings,then tap your foot,and so on to give it color.:)