 One way to train the hand to unlock 1 & 2 is to place a pencil between 1 & 2 with the other end behind the thumb while playing.Classical guitarists have a different set of left hand calluses on their fingertips than the steel-string players.In the steel-string, played with the guitar under the arm and on the right hip (called 'playing off the hip'), the left hand fingers of the steel string guitarist play on the diagonal, or 'for the reach', and the fingertip lands on the pad of the finger, forming a callus on the pad.