This is a trick that most of the PowerPoint users are not familiar with. You might be working with slides having different orientation (Landscape/Portrait), there isn’t any straightforward solution to use slides with different orientation in the same presentation
Hyper-linking the two Presentations
1. Open your first presentation having the landscape slide, add a blank slide with a title or any other element, your presentation will be displayed in portrait format
2. Select any object, Right Click on it and choose Action settings. Choose Hyperlink to, click on the Other Presentation tab and browse to your second presentation having the portrait slide
3. Choose a title for the slide from the Slide Title list which appears as an anchor text for the hyperlink
Repeat the same process in your Second presentation (Create a hyperlink from the second presentation and choose an appropriate slide title
Insert Object Method
If you find the first method unprofessional, you can use the insert object method which looks much cleaner
1. We are going to use Linking and Embedding (OLE Object Linking and Embedding) technology. In your first presentation, on your landscape slide, Click Menu Insert – Object
2. In the Insert Object window , select From a File and click Browse to select your second presentation file. Click OK
3. You may see a blue rectangle that represents the image of the second presentation. If you want the image to be visible to the audience, leave it as is. If you wish to hide it, drag it into the gray area .
4. Select the rectangle (2nd presentation object) and click on menu Slide Show / Custom Animation pane to display animations list window on the right.
5. Click Add Effect, configure the animation and transitions such that clicking on First slide directs you to the second slide (with different orientation) and vice versa
Let me know if you encounter any problems, i will help your through it