The sixth-string notes are slapped with the picking hand’s thumb [indicated by S], and the fourth- and fifth-string diads—the little two-note chords—are “popped” [indicated by P] with the middle and index fingers. “On the pops, try to get as much power from your wrist as you can so that after you pull the strings away from the fretboard they really snap back down hard against the fretwire,” adds Morris. “Licks like this sound great on an acoustic guitar, since you often get some extra thud factor from the contact between your hand and the guitar on the slaps. Heavy strings will maximize the percussiveness of your sound and often actually make the execution of percussive techniques easier.”