Finally, save your work as a template that you can use over and over again. Before saving, return to normal view and be sure that you have only a single slide there. (In master view, it's okay to have both a slide master and title master, or as many masters as you want. But in normal view, you should have just the default slide, with no extra slides added.)
Rather than saving your template as a .ppt file, which is the default, save it as a Design Template (*.pot), and give it a name that you will recognize. Save it to the default location that PowerPoint opens for templates.
After you close and reopen PowerPoint, the design template will be available in the Slide Design task pane in the Available for Use area.