Hi Thunderkattz,
"I can't have an archive section in the blog if I've only had it up for a day!" You don't need an archive right away. People won't want to read an empty blog that only has 1 entry however you have to start somewhere.
You just start writing articles for your blog. Write 2 today, 2 tomorrow before you know it you'll have a dozen blog posts and content 2 or 3 pages deep. (Depending how long each one is and how many blogs you set per page.)
Once you have a dozen, you have enough content that it will start to take shape. After that try to blog at least once a day.
Did you pick a niche you know about and are passionate about? If so then think about the types of things that would interest you and write about them. Or do research and find out what other people in your niche are writing about.
Often what people do instead of always having to come up with articles from scratch - is to research the news in their niche or find an blog post that they think would be of interest to their readers. Then they just write a preface or add commentary or share their viewpoints and then quote a small portion of the article and link to it. So it's more like you are a news reporter and covering and adding to an existing article someone else already wrote.
For example here's a blog post I did which was a story AROUND a story that someone else wrote.
I just added my thoughts about their story.
Obsessive Compulsive ADHD Affiliate Strategy
So that's just one way to start generating some content if you can't think of enough content to write from scratch.