A – Assess what happened. Ask yourself, Why am I upset? Pinpoint the precise cause so you understand what’s making you feel this way…. State the facts as objectively as possible so you’re articulating the catalyzing event(s).
N – Nix extreme words…. Extreme words produce extreme emotions. “All or nothing” words escalate anger.
G – Give a specific example. The more precise you are, the more productive you’ll be. Instead of “You never think of anyone but yourself,” identify the particular action you perceive was inappropriate. “You took the car today without asking if I needed it, and I was left stranded.”
E – Express the desired behavior instead of criticizing the dreaded behavior. Complaining about what they did won’t undo it. It’s more effective to clarify what you want from now on. Perhaps you can say, “From now on, if you need the car, please ask what my plans are so we can coordinate things.” This step helps you bypass any ego needs to go into how inconvenienced you were and how inconsiderate they were.
R – Review to make sure the point got through. Trying to have the last word – “This better not happen again” – creates more conflict, as it’s a battle for control. Ask this person to clarify how they’ll do things differently in the future so there is a verbal commitment to changed behavior.
— Sam Horn in Talking on Eggshells