Self-running PowerPoint presentations don't require any user input so they can be used to display information at a tradeshow, for example. Any presentation can be configured to be self-running and to do so, first set the slide timing by selecting all the slides and choose click the Transitions tab and, in the Advance Slide area disable On Mouse Click and select the After checkbox. Set the default number of seconds for the slides to show on the screen. If any slides need to be shown for a longer or shorter time adjust this time for that slide only.
To set up the show click Slideshow > Set Up Slide Show. From the Show Type options click the Browsed at a kiosk (full screen) and from the Advance slides list select Using timings, if present and click Ok. Now, when you run the slideshow it will run automatically and it will loop when finished and replay repeatedly until you press Esc.
For best results, ensure that any animations in your presentation are set to play automatically so they don't require a mouse click to appear. Also disable your computer's screensaver so it won't trigger due to keyboard inactivity.