If you're familiar with the Choose Your Own Adventures book format, this structure should be obvious. After reading each page, select the action you'd prefer to follow. The link will take you to the next appropriate page. Your story may end after one (good or bad) decision, after five choices, or possibly after ten.
To avoid spoiling any surprises, I recommend using the link below to get started. Alternately, you can go to the page labeled The Emergency - Start Here! Either way, your browser will only load the current page and you won't accidentally see a page too early.
It's very tempting to look at all the possible endings of a Choose Your Own Adventure story, but try to wait until you've chosen a few full storylines on your own. Some endings might not make as much sense out of context. You might not know which decisions lead to which endings. Some endings even contain clues to help you make better (or worse, but more interesting) choices on a future reading.
Last of all, there are a lot of pages. Trees end up with many leaves. If you try to read everything in order, you get a lot of gibberish. Sorry that the month's page listing is ridiculously long as a consequence.
Blogger isn't the ideal site format for something like this, but one of Laine's and my goals for this site was to explore how technology could influence our writing and science-fiction writing especially. This story is one of the big projects I've been hinting at for some time. I hope you enjoy both the novelty and the experience itself.