One breath before answering is enough to change what gets said. It isn't mystical — it's just long enough for the second thought to arrive, and the second thought is nearly always kinder than the first.
Compassion built this way accumulates in very small units. A breath here, a re-read of a message before sending, a decision at half past six not to say the accurate thing. None of them feel significant on the day. Over a few years they amount to a different person, in the way nobody notices a hedge growing and everybody notices it has grown.