Open the Slide Show menu and select Slide Transition to open the Slide Transition task pane.
In the Apply to Selected Slides list, click the transition effect you want to use. You can modify the transition with the Speed and Sound lists.
Click the Apply to All Slides button to apply the slide transition to all slides in the presentation; otherwise, see the tip on this page.
Click the Slide Show button to see what the effect will look like on your presentation (move through it like you did in the previous task, "Viewing a Slide Show").
INTRODUCTION
Slide transitions can make your presentations look more professional and interesting. For example, having each slide appear to open like a vertical blind draws the attention of the audience. It's generally best to use only one type of transition in a presentation because using more can distract the audience from your message.
TIP
Additional Effect Options
If you want a special transition effect for a single slide, open the slide, select the effect, and select to apply it to the slide instead of to all slides. You can also change how you move to the next slide for example, you can select On Mouse Click or Automatically After (you select the number of seconds).