Watch the Minor Triads online guitar lesson by John Stowell from Modern Jazz Improv

As I mentioned here, pay attention to the minor modes that the different minor triads touch on, and eventually combine them with other substitutions from those modes (i.e., D minor triad/Eb major arpeggio/C Dorian, Ab major arpeggio/Ab minor triad/C Aeolian and C melodic minor). Eventually put these sounds/substitutions in a simple context such as a minor blues to develop familiarity with the harmonies.