Hmm... it took me a bit to discover how to add to the blog. Here is how you do it:
1. In the upper right corner of the page you should see "Create Blog" and "Sign In". You do NOT want to select "Create Blog" as this will make a whole new blog, not add to the "Nifty Fifty" blog which has already been created (thanks!) for your blogging pleasure. No, rather, you should click on the "Sign In" link, and enter your username / password if you haven't already.
2. You will now see a list of all the blogs you are subscribed to. In my case, I only have "Nifty Fifty" there but some of you may have more. Below the title of the blog you'll see a nice green plus sign and some verbiage that tells you to click there to add to the blog. Do so, and you are brought to an edit page where you can enter a title and a message.
3. Note the little do-dads above the edit screen. This will allow you to change colors, font, formatting, etc. as well as adding a picture.
4. If you know your web development, you can also click on the "Edit Html" tab to further refine your code, but this really is only for advanced writers and can be overwhelming for the average blogger. And, hey, beside that we really want to read your words, not be overwhelmed with all kinds of your fancy HTML coding.
5. Once you are done, click on the orange "Publish Now" button and you will see your text posted on the blog.
6. Wash, rinse, repeat.
On the blog itself, if you read something interesting posted by another, you can comment on it! All you need to do is click on the "Post a Comment" or "0 comments" link, enter your comment in the "Leave your comment" field , and then click on the orange "Publish Your Comment" button.