In a time where communication is readily pervasive, we have become overwhelming casual with our conversation. The terms formal vs. informal are things of the past, as the two mesh into one. The forum of writing in informal platforms has left us with a informal approach to communication. For example having an argument via text message might not be the best choice of vehicles due to the nature of high emotion and greater chance that intentions will be lost in translation. This is a very easy way to avoid unnecessary confusion.
I recently have challenged myself to press into the idea of clearly labeling conversations as "in person", " phone", or "text" just to maintain the clear differences between them. I've even gone a step further to intentionally 'switch' hats (roles) in the midst of a conversation, so that my responses are always in order. Case in point, when talking to a supervisor you might initially start the conversation with one line of thinking and then shift due to the complexity of your relationship...a boss that's also a friend. Before attempt to respond or answer a question as a friend, let the other individual know that you are now switching gears and would like to share from that space. It's just less muddy this way.