For those of you that eventually want others to talk about your blog, the bio should but be placed prominently either close to the top of your blog or with its own page. Your explanation of yourself does not have to be especially clever or funny but it should be succinct. If your blog is about cooking, say something about your interest in food, not that you live with fourteen cats.
As you blog you can share more about yourself but the author bio is a quick way for people to get a 2-3 sentence impression of you. Allowing people to associate an author name with a blog will also help if you choose to expand in to different projects such as starting another blog.
So don't be ashamed. It's your blog and you should let people know it!