Establishing Your Baseline Virtual Body Language
Learn to type. It may sound silly, but if you're someone who isn't used to typing a lot and you suddenly find yourself in a position where you are forced to rely on typing to convey facts, thoughts and opinions, chances are you've got pretty poor virtual body language to start off with. When people struggle to respond via text, email or IM, it can send all kinds of wrong signals. So make sure you're comfortable with typing or texting, and that you can do it at a decent speed. Responding fluidly is very important and can help show that you are involved in the conversation and that you are giving the other person your attention. Practice typing and texting to get up to speed, especially if digital communication is a key facet of your job.
Leave the shorthand to the pre-teens. While it may seem faster, shorthand typing takes longer to read, comes across as sloppy and removes a lot of elements that you need to communicate effectively. That means no more "u" instead of "you" and no more convoluted acronyms. After all, it shouldn't take ten minutes to decode a text that you sent in fifteen seconds.
Spelling, grammar and punctuation are critical. Most people who type or text can be incredibly forgiving when it comes to the occasional typo—we all do it! However, if you're someone who can't spell to save your life, it's time you start to learn. Of course, you can always cheat and use spellcheck. Several IM programs now have a spell checker built right in, as do most email clients and smartphones. So, when you see spellcheck chime in and tell you something isn't right, make sure to change it.
As far as grammar goes, try to type as clearly as possible. Avoid using too much slang and take a few minutes to re-read what you've typed. If something doesn't sound right in your head, read it out loud a few times. Chances are, if you're having a hard time understanding what you're trying to convey, someone else probably will too.
Using punctuation is absolutely key as well. Sure, it might save you a fraction of a second to forego typing that comma, period or exclamation point, but when the person reading your paragraph of text has to try to parse it into separate phrases and thoughts, it's not worth it. Punctuation is one of the most important things when it comes to writing. It allows you to separate thoughts and ideas and even convey emotion. Leaving it out is just asking for trouble.
Avoid playful sarcasm whenever possible. Because there's no vocal cues, sarcasm comes across very poorly in text. You could easily confuse or even potentially offend someone when you think that you're just being playful.