Locate the brown dots at the 5th, 7th, 12th, 17th and 19th frets. For instance, above each set of 2 fingerboards are 4 related keys. The gray area on the end are the open strings. If the first chord of a song is C Major, like the chords: C Am F and G, improvise with these hand positions using C Major fingerboards or C Major/m7 fingerboards. Usually, the first chord indicates the key. If the chords of a song begin in Em, use the fingering for E minor or E minor/Maj6. Every note showing would be in that key, no matter which color hand position you play. Try it.