It has taken me a few years and I still fail sometimes, but I have learned to let people finish and then ask questions instead of telling them they're wrong, even when it's totally obvious to me. "What if that fails in this way?" instead of "that will fail in this way!". It makes the discussion collaborative instead of assuming that it's my job to point out everyone's failures. The punch line in one of my favorite comic stips is "It's not healthy to keep your problems bottled up inside me." It took me a long time to see how that applied to my own interactions.