PowerPoint offers a couple of options for previewing an animation effect on a slide in Normal view. There is a Preview button on the Animation toolbar that plays all the effects on a slide, and the Custom Animation task pane offers a Play button to play the individual animations on the animation list. There is also a Slide Show button in this task pane to quickly go into Slide Show view.
With a slide containing animations displayed, click the Animations tab.
Click the Play button to play the applied animations in sequence.
To view the animation in Slide Show view, click the Slide Show button at the bottom of the Custom Animation task pane.
To stop the preview from running, click the Stop button at any time.