We can name four means that promote the perception and memorization of what is heard:
First, you should acquire spiritual firmness and determination;
secondly, you should heed wise counsels attentively and with an open heart, eager to grasp the meaning of what is said;
thirdly, you should ponder over these wise words and repeat them over and over again so as to imprint them in your memory;
fourthly, you should avoid harmful states of the mind and resist them even in the face of temptation.
These states of mind are: careless sloth, indifference, senseless amusement, the inclination to morose reflection and destructive passion. These vices can destroy both your mind and your talent.