A simple exercise, borrowed from giraffe language / non-violent commenucation. Describe what happened in a way, even your worst enemy would have to agree with. This means sticking to what you saw, heard etc., without lumping things together or including judgements.

So, if your friend and you were to meet at the cafe at 13.00, and he showed up at 13.05, there's not much else you can say about that situation. You can't deduce a motive for his being late, and it wouldn't be wise to lump this being-late together with other being-lates.

Exercise based on this: 4 people work in 2 groups. A will tell B about some incident or period of her/his life. C will talk to D. Then B talks to A and D talks to C. Then the 2 groups merge, and B gets to retell A's words. Unless B is specific, A will have reason to correct summaries and judgements. Then A, C and D retell their partners words.