To expand on that with "obvious" advice: Know your audience. Present accordingly.
Are you an expert or a beginner relative to your audience? If I'm explaining something technical, I might take a more assertive tone when glossing over details with a novice but speak with more deference to an expert. (e.g. Throw in a few "I think ..." or "My understanding was that ...")
Getting a quick grasp of where the speaker is coming from helps the listener really engage at the right level. Should I double check what the speaker is saying or are they the authority on the matter? Nothing get's eyes rolling faster than someone making blatantly wrong factual errors overconfidently.