Head for the Site Center and make sure you're on the Pages tab.
Drag and Drop
Two orange dots will appear when you hover over sections and pages. Move your cursor over these dots, click, hold, and drag to the desire location.
However, you can only drag and drop items at their current level of the site map. To move items above or into another item use the Move button.
Use the Move Button
Select the section or page you wish to move and then click the blue Move button. Choose the destination from the with that appears and click the OK button.