Here is my first tip on starting a blog...figure out what you want the point to be. I am probably not the best example of this, as I tend to blog on a variety of topics, but I am very impressed with people who are able to maintain a consistent theme or way of tying things together.
Of course, an obvious way of doing this is only blogging on one topic (ie: gardening, dating, Apple, etc.) A great example of this is CakeWrecks. Every post is about cakes, and they are hilarious. I've also seen bloggers pull this off by ending each post with a similar closing or connecting each post with a song title/lyric. It's a great way to show off your creativity.
People get comfortable with the familiar and it's an effective way of drawing them back. These features become characteristics that your readers will hopefully come to know and love about your blog. The design and name of your site should also reflect its purpose. I'd love to get a custom-made header that emcompasses what my blog's about, but for now I've got to stick with the options Typepad gives me. Luckily, they have a lot of variety!
If you're like me and write about many topics, don't worry about trying to make every post fit into a certain mold or genre. Many of the blogs I enjoy the most write on everything from parenting to current news items to whatever strikes their fancy. And it works! The most important thing isn't what you write about but how you write it.
