1. Cream of Crop. Twitter is not a complete braindump of everything that happens to you throughout the day. It's not IM'ing from your subconscious. It's for the gems. The best. The top events, thoughts and things you come across. It's the stuff you would write home about. Everyone is looking in and if you send too much stuff that isn't worth looking at, you'll stop being followed. You can get a lot and it's not meant to be an exact medium, but there is a point where you miss good stuff because of the bland stuff.
2. Occasionally Personal Qwirky. Once in a while, maximum once a day you can throw in a little bit of individual life. Like, "Back from they gym and I'm really really tired." That's fine. Mix it up a little. Let us know you're human. Just don't tell us every little thing that happens. Don't twitter "Morning" "Coffee time." "Good coffee" "Back to work" "Hungry..." "Reading a website" "Checking emails". I'm really not interested, if other people are and I'm too 1.9 then OK, fair enough, but I think it applies.
3. Remember the Invisible Audience. Your Twitter crowd is vague and changing. Not everyone watches, not everyone reads every message, not everyone follows everyone. Responding "Oh, that's funny." when half the people don't know what was funny is disastrous.
More Twitter guides here and here.
Discuss it Here