Chris said not to share this list but also said that every rule on this list was breakable so here is me breaking the rules and sharing the list anyway. My favorite is #3:
I'm a bit biased but I truly believe everyone should have a blog. And a Twitter account.
One thing I can not back fully on this list is #2. Pick an area of focus. If you want to be successful at blogging - and that usually means building a fairly-sized audience and making money - then yes, pick an area of focus. For me, at the moment, that's The Watercolor Gallery. Laser-focused blogging. Crazy successful. Much more successful than this blog.
But, I also think that if you just want to maintain a blog. Don't worry about an area of focus. This, my personal blog, is about whatever I want. Whenever I want. However I want. It gets almost no traffic and generates about $50 bucks a month. And I'm tickled pink about it.