I've learned to manipulate my body into feeling anger without being angry,listen to music like Hollywood undead, find one that you feel that it's angry, and play a reaction game like fruit ninja, your body will be stimulated and it will go into flight, your adrenalin glands will release and you'll feel like a focus and sort of rage manifest.your body will release the frustration. It's like your between full rage and serenety it's fenominal