Here are seven simple rules to follow when starting out on Twitter. Although they are mostly "don't do this" thoughts, don't let that dissuade you from using it. Using Twitter is just like using a website - there are things you do and things you don't… and it's mostly common sense. Most importantly of all, have fun with it!
1) You may not know it, but you're already tweeting - you're just using your mouth instead of Twitter. All your nuggets of knowledge/wisdom/insight are interesting and people want to hear them. You already give them to employees/partners every hour of every day… just tweet them - don't say them. This doesn't mean you have to give away all of your knowledge, just the bits and bites of value that are not intellectual property or trade secrets.
2) Feel free to share subjective opinions - not everything has to be academically proven. Opinions are fine, people get it.
3) Do not tweet things that are too personal. This isn't your home, It's your business. It's OK to put your personality into your tweets, but stick to your workplace personality, not your "back office/water cooler" personality.
4) Do not post anything you don't want re-distributed. Assume media (Winnipeg Free Press, Globe and Mail, etc) are reading your every tweet.
5) Every one of your tweets will live forever, even if you erase it. Be careful!
6) Have fun with it and watch what other people are tweeting. Follow some brands/people that you like and remember that the people/brands you follow say something about you. Watch not just what they say, but how they say it (learn the lingo).
7) It's OK to make a mistake - if you do, admit it and then apologize and move on. The worst thing you can do is to ignore a mistake or add to it by lying about it.