You want him to hang a shelf? Mow the lawn? Asking her to throw in a load of laundry? Make sure you ask, rather than demand. We all tend to respond better to requests than orders. For example, instead of saying, "You should...," say, "Could you...?" And instead of saying, "Why didn't you...?" say, "Next time it would help me if you could try to..." If you're the one being asked, deliver on your promises. Failing to keep your word can destroy the unity and trust in a relationship. It's better to say, "Let me think about it" than say you will do something but drop the ball.