This is written for the Newbie Blogger Initiative, which is going on throughout May 2012. You can find more info at http://nbihq.freeforums.org.
Trademarks aside, that's the best advice I can give a new blogger.
Just go ahead and write. Don't be afraid.
Well, be smart. Don't write things that'll get you in trouble at work, or with your family, or with your friends. If you want guild drama, the easiest thing to do is start posting about the scuttlebutt in your guild and what you think of it all. If you wonder whether something you're writing is going to cause trouble, skip it and come back to it later.
If, however, you really don't care what people think and you've got the intestinal fortitude to back it up, then damn the torpedoes!
I realize that people will say to write what you know, and yes, that does let a new blogger start out on familiar ground. But for my money, the act of writing itself is more important. You're only going to get better as a blogger and a writer if you challenge yourself, by pushing what you can do. When I look back at my initial columns when writing PC, I cringe. I had no idea how little I knew about WoW, and what I thought then was decent writing now seems really klunky and pretentious. Do I wish I'd been a better writer back then? Sure. But the thing is, the only way I really did improve was to work at it: I played more, learned more about the game, and I wrote.
When you write, a funny thing happens. You gain perspective. You analyze yourself and what you believe. You realize that not everyone will agree with you. Hell, you also realize that what you thought was pretty good might be utter crap to another person. Or worse, boring as sin.
Don't go into this because you want to be an awesome! cool! popular! blogger, because that's lightning in a bottle. You can't chase fame without sacrificing yourself in the process. Instead, blog because you want to, and because you have words that want to come out. When you blog like that, you're exposing more of yourself than if you were chasing fame, but in that risk lies the reward.
A blog is a strange thing. It's composed of your writing, and it can live indefinitely if you want it to. It doesn't need readers to survive. What it does need is a blogger.
Don't worry about readers. Don't worry if it seems you're shouting into the wind. Concern yourself with what you can control, and that's the content.