Don't hide your real thoughts
Communication consultant Kirk Livingstone believes that the most fruitful conversation starts with the willingness to share what you're really thinking and feeling. 
This doesn't mean you blab your gnarly anxieties or last night's dream with your new co-lead on a project. It does mean that if the topic is the timeline for phase one completion, you share what you really think or feel about phase one completion. The opposite might look like agreeing with everything when you don't mean it. Or disagreeing out of habit. Or not saying much because you're afraid of seeming naive or bossy. Instead, own your take.