Remember that people have varying communication styles and that not everyone is using their native language. (Meaning and tone can be lost in translation.)
Productive communication requires effort. Think about how your words will be interpreted. Remember that sometimes it is best to refrain entirely from commenting.
Avoid derailing: stay on topic; if you want to talk about something else, start a new conversation. Avoid unconstructive criticism: don't merely decry the current state of affairs; offer—or at least solicit—suggestions as to how things may be improved. Avoid snarking (pithy, unproductive, sniping comments) Avoid discussing potentially offensive or sensitive issues; this all too often leads to unnecessary conflict. Avoid microaggressions
What you say and do matters. Take responsibility for your words and actions, including their consequences, whether intended or otherwise.