When one is ready to add a new slide to a presentation, there are two ways to accomplosh this. The first method is to use the New Slide button located on the toolbar. The button will look like a blank, white slide with a star.

Click on this button and the Slide Layout dialog window will appear with several options to choose from. Select the one you want by double-clicking on the chosen layout and the new slide will appear on the screen.

The other method is through the menu bar. Click on Insert in the menu bar and then click on New Slide. Again, the Slide Layout window will appear.