When you create a page, don't tick the box that makes it visible to all. When you're finished with it, tick the box. If you're sharing progress with other people you can either tick the box to allow registered people to see pages or make your own special roles and assign people to them.

Or you could make the pages visible to all, but just not add the pages to an existing menu, meaning they won't be easy to find unless the person knows the exact URL... then share the URL with people who need to see them.

Have a good look through page page settings when you create a new page and see what the options are.

Rob