First. Decide that you will allow yourself to feel any emotion without interference, but not act upon it.
Live your life as usually. When something happens start noticing. Feel it and describe.
"Fuck. Bastards. What are you doing. Stupid monkeys." I am angry on this stupid guy who did that. But I'm not doing anything. Why am I angry? What am I afraid of?
You find the fear and start analyzing it.
I'm afraid of stupid people because they are irrational and may do stupid things. I'm affraid they can harm me and I won't be able to control them and stop.
Ok. I need to work on myself to become stronger and more resilient. Also, I can preplan my actions to not allow dumb people around me.
Most emotions start with fear. Feel them. Analyze. Find the fear. Make changes and become better.