How can you learn to control your anger?
Through conscious and repeated practice.
All our habits and skills are the result of our repeated actions. Our daily actions shape our emotional and mental dispositions. If you feed your anger through impulsive reactions, you reinforce this tendency and make it harder for yourself to stay calm in the face of future provocations.
If, on the other hand, you make a conscious decision to curb your anger, you will gradually weaken this habit.
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“Every habit and faculty is confirmed and strengthened by the corresponding actions,
that of walking by walking,
that of running by running.
If you wish to be a good reader, read;
if you wish to be a good writer, write.
If you should give up reading for thirty days one after the other, and be engaged in something else, you will know what happens. So also if you lie in bed for ten days, get up and try to take a rather long walk, and you will see how wobbly your legs are. In general, therefore, if you want to do something, make a habit of it; if you want not to do something, refrain from doing it, and accustom yourself to something else instead. 5The same principle holds true in the affairs of the mind also; when you are angry, you may be sure, not merely that this evil has befallen you, but also that you have strengthened the habit, and have, as it were, added fuel to the flame.
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If, therefore, you wish not to be hot-tempered, do not feed your habit, set before it nothing on which it can grow. As the first step, keep quiet and count the days on which you have not been angry. "I used to be angry every day, after that every other day, then every third, and then every fourth day." If you go as much as thirty days without a fit of anger, sacrifice to God. For the habit is first weakened and then utterly destroyed. "To-day I was not grieved" (and so the next day, and thereafter for two or three months); "but I was on my guard when certain things happened that were capable of provoking grief." Know that things are going splendidly with you.”