The answer you want is already in the question. To anger you don't have to respond or resist. That's it. You need, as Huda already said, to take a deep breath first of all. This will occupy some time that would have been spent, by you, to react impulsively to the anger. Angry people are really effective to fire up your anger, they just want that. Moreover, if you stay calm, the one you're talking to will start to calm down because an angry conversation can go on only if both people are angry.

It is not always as easy to offer an answer, because different people have different abilities and different was of coping. Generally however, there are several common strategies. #1 Cultivate a feeling of love and understanding, recognizing that most social primitives react emotionally, and anger is the common emotional reaction the social primitives resort to. #2. Engage in deep and visceral breathing, drawing each breath deep down into the solar plexus. and exhale slowly and calmly before taking another breath. #3 Offer an affirmation of the angry person's communication, informing them that you are convinced that they are justifiably angry. (Whatever you do, do not stare in silence like a cow at someone if you suspect that they would appreciate some sort of verbal response such as a "Yes Sir" or a "Yes Man". Speak up and open a line of communication with the other person. Encourage them to fully express their idea. [Remember what the Godfather said in the movie: "Keep your friends close, and keep your enemies closer!" ....or something to that effect] .

You can take a deep breath, and think about positive things. Also, relaxing and meditation are effective methods.