Use the Random Slide Show add-in
Download and InstallationIf you downloaded the executable, double-click it and follow the prompts to install the add-in in the folder of your choice.
If you downloaded the zip file, unzip it and extract the files to a location of your choice.
Office programs have a default location that might be an useful location for this add-in. The location of this folder has changed with different versions of the software. To locate this folder on your computer, open PowerPoint, then select Tools | Add-Ins (or the equivalent in PP 2007). In the Add-Ins dialog box, click the Add New.. button. This will open in the default folder used by PowerPoint for add-ins.
To ensure you use the correct
security settings and to install and load the add-in, see
Common Installation Instructions for Office add-ins
http://www.tushar-mehta.com/excel/software/installation/index.htm
In PP2003 (or earlier), select the menu item TM | Random Show► Random Slide Show...

In PP2007, select TM | Randomize Slideshow | Randomize.

This will bring up the Randomize Slideshow dialog box.
In the dialog box, specify how
many of the initial slides should be shown in their original sequence
(i.e., not subject to the randomization process). If there are
no slides that must be shown at the beginning specify zero. the showing of
introductory, credit, and summary material in the correct sequence.
IIt is also possible to specify whether to run the slide show immediately and/or to save the randomized slide sequence. The add-in creates a custom show named _RandomSlideShow containing the slides in a randomized sequence. If the custom show is not to be saved, the add-in will delete it when it is no longer needed.
