Blog...

You can also use Wordpress at http://wordpress.com/. Its very easy to use and you can change the layout, look and feel of your blog. They have great guides to starting blogs etc. How often you update your blog is up to you. If you are wanting to make money from your blog then obviously one post a year isnt going to get people coming to, and coming back to your blog. Regular blogging helps. Try to create a blog based on an interest or something specific that way it will help you create a better blog and readerbase.