Building a lifecycle template and connecting pages to it is a multi step process. Step 1 requires you to add a content type called Lifecycle template page. While creating the page, you need to link the page to the website's top navigation bar (then disable the link so it does not show up to a user). Step 2 requires you to add pages to your lifecycle (which, when linked together, add a menu on the left) and link these to the original Lifecycle template page so that the navigation buttons show up on the left of the lifecycle. Step 3 shows you how to add a sub-page and link to the lifecycle. Step 4 shows you how to fill with content.
Click through these steps (at left) to learn the details of how to build a lifecycle page group.