Go to Configure Site > Social Networking > Timeline for the Timeline configurations page.

On this page, you can configure which posts get displayed on the timeline pages - by who and which type - which features to use, customize the phrases, and customize the display.  Also, on the top of this page you can get the Placeholder Text to copy/paste onto your Pages > Add/Edit Page to display the content.

Use the "Timeline" Placeholder Text to display content from more than one users.  Use the "Timeline - Member Profile" Placeholder Text to display content for the member.  If a member is not specified for the Timeline Member Profile page, the member is the logged in member.  To have a member specified for this page, (1) Copy/paste this Placeholder Text onto a page, (2) Set this page as the Public Profile page on the Configure Site > Social Networking > Profile > Public Profile page - then, when a user clicks on a username/user's link, they will be directed to their member public profile page which includes this timeline page content.