Expressing Tone in Text
Perhaps the hardest lesson to teach about internet etiquette are the subtle things like tone. How do you best show emotions in your emails? Should you use sarcasm or make jokes? How can you express yourself so that people understand what you mean?
It's actually hard to perfect, and it takes a lot of practice. Communicating on the internet often leads to misunderstandings. People will try to make a joke and come across as sarcastic and mean, or people will send a simple, perfunctory email and will be portrayed as cold. That's the very reason that emoticons (otherwise known as emotes or emojis) came to exist. They're a way of showing emotions or making it clear that you're joking, and they work well in informal communication as long as you don't use too many. However, they're not appropriate in formal emails. So what do you do then?
The best advice is to be really careful how you write. If an email is important and you have time, write a draft and read it back a few hours later, or even the next day. Find a balance between professional and relaxed, business-like but not cold, and make sure that your tone and meaning is truly clear from the words alone. When in doubt, avoid sarcasm, controversial opinions or jokes, and anything that could be misinterpreted.
Remember that everyone you're talking to is another human being. Treat them the way you would treat anyone you met in-person. One of the biggest mistakes people make on the internet is saying and doing things they wouldn't do in real life, so don't be that person. If other people make etiquette mistakes, remember that they're human too!