Maybe you simply want to mix things up. Or perhaps your presentation data lends itself more to a portrait orientation. Either way, you can change the orientation of your slideshow slides from landscape to portrait.
First, ensure you’re in Normal view. Open your slideshow and select the View tab on the main ribbon. In the Presentation Views group, click on Normal. Next, select the Design tab on the main ribbon. In the Customize group, click on Slide Size. Choose Custom Slide Size. In the resulting Slide Size dialog box, click on Portrait in the Slides area. Click OK. In the resulting Microsoft PowerPoint dialog box, choose to either maximize your view, potentially losing some data around the edge, or you can ensure that all data will fit on the slide.
Be aware: This technique changes the orientation of every slide within a slideshow. You can’t switch between portrait- and landscape-oriented slides within the same presentation.
When designing a slide, you often have to rearrange objects as you introduce a new design. And if you ever needed to move an object in only one direction (either horizontally or vertically, but not both), then you know that it can be a real pain in the neck using the mouse. If you select the object and drag it using your mouse, no matter how careful you are, usually the object shifts slightly in an unintended direction. Alternately, you can select the object and move it using the arrow keys to keep the object in line, but if you need to move the object clear across the slide, then this is an impractical and time-consuming method.