First of all you should change your position and body posture whenever you get angry that means just sit down if you are standing, or lie down if you are sitting etc. Drink a little amount of water, try to contemplate the consequences of the anger and think about future that what will be happen after a few minutes if I get angry now. Also recite the following supplication as much as possible especially after prayers to get power from Allah to control your wrath. اللهم صل علی محمدٍ و آل محمدٍ. اللهم اغفِر ذَنبِی وَ اذهِب غَیظَ قَلبِی وَ اَجِرنِی مِنَ الشَّیطانِ الرَّجِیم و لا حَولَ و لا قُوَةَ اِلّا بِالله العلی العَظِیم.
Best is you do Astagfar and recite salwat