When you add a slide, you choose among different slide layouts that are based on your presentation’s theme.
Add a new slide: Tap 
at the bottom of the slide navigator, then tap a slide layout.
Copy and paste an existing slide: Tap a slide in the slide navigator, then tap it again. Tap Copy, then tap anywhere in the slide navigator and tap Paste.
Tip: After you tap Copy, tap the slide again to paste its copy immediately after it.
Double-tap placeholder text and type your own.
Tap 
in the bottom-right corner of a placeholder image to see the photos available on your device.
Tap an album, then tap an image to replace the placeholder image.
To change which part of the image is visible, double-tap the image, then use the masking controls to make changes.
Tap Done.
To learn more about how to mask an image, see Add and edit images.
Tap a slide in the slide navigator, then tap it again and tap Delete.