The second key is understanding that all people are really your reflection, what i mean by that is if someone is annoying you or making you angry chances are the reason lies in you and not in him. If you weren’t angry to begin with you would simply laugh or walk away when someone would try to irritate you.
Usually the reason people try to make you angry is so you do something like yell or curse them and then they can take their anger out without feeling guilty.
Once you understand that the other is only an excuse, meaning he isn’t the reason your angry ,and that he is actually helping you by showing you areas in yourself you need to work on, you could stop blaming others for your anger and forgive them for their behavior, because you will understand that they are doing this out of their own anger and pain.
when you feel anger don’t block it as a bad emotion,instead try to take it out in a healthy way like screaming,sports, or just hitting a pillow. All emotions have a natural place and when expressed are perfectly healthy,but if you stifle the anger it becomes rage.
Forgive others for hurting you, do it for yourself because anger and grief that kept inside create diseases. here is a similar video that helps with anger.