So, you're a small business owner entertaining the thought of laying your money down (only $20/month) to start blogging. Your next questions are, naturally, when should I blog and what should I blog about?
When to blog - Daily, definitely. You can't engage in the conversation if your voice is silent. You should also consider (especially if you're a once-a-day blogger) posting to youe blog at about the same time everyday. Let your readers (customers, prospects, etc.) know they can rely on you to dispense quality information on a regular basis and they will come to rely on you. Draft posts that you return to in order to work on and refine can be scheduled for publication on a certain day and time. Take advantage of this feature. If you're feeling especially creative and energized, draft a group of posts and try to finalize and schedule as many as possible. These soon-to-be-posts will serve you well when life inevitably gets in the way.
You should be blogging, at the very least, once per week. If you can't muster up at least one post per week then perhaps blogging should be reconsidered at a later date. You'll want to put thought and planning into your posts, but don't spend too much time staring at a blank screen trying to come up with something to say. When writer's block (or blogger's block) inevitably does arrive, a good blog consultant (such as Small Biz Blog Wiz) will council, guide and advise you on certain ideas and types of blog posts so that you should never be without something to say.
What to blog about - Depending on your business niche you may want to consider blogging about: Who you are - you need to tell your business's story over and over and over again before people event begin to listen. Always tell the narrative of your company - why your business is, or will be, the absolute best company for people to deal with. Prove yourself in actions, and then blog about those actions. What sets you, the business owner, apart from your peers? Let people in on your genius. Make it interesting, emotional and personalized. You will more easily gain readers in a conversational tone (aha!) than you will if your blog sounds like your brochure or radio ad repackaged for online publication.