This solution applies only to websites using one of the Deluxe Ready-to-Go Website packages: Ames, Baxter, Charnock, or Flavel. It applies specifically to pages using the template called "Child Pages":

To specify the order in which the child pages appear on this page, you need to go to each child page and input a number in the Order field in the Page Attributes box.

For a slightly quicker process, you can use the Quick Edit feature on the pages screen:

Input a number into Order, then click Update

Please note: You need to fill in an order number for each of the child pages. Then the parent page will order them from smallest number to largest.