It is very easy to change the PowerPoint theme for the existing presentation. Here’s a short tutorial on how to do it:
- Inside the slide canvas of your PowerPoint presentation, head over to the top menu bar and click 'Design'.
- Following that, go to the Theme Gallery and click the drop-down arrow below it to view the collection.
- Choose the new theme you wish to set.
- Finally, the default PowerPoint theme of your existing presentation will be changed accordingly.
