Open the Slide Show menu and choose Custom Animation .
PowerPoint opens the Custom Animation Task pane. Click the effect you want to reorder.
Click the Up or Down Re-Order button to change the effect's order in the list.
PowerPoint moves the effect in the list.
If you assign more than one custom animation effect to a slide, you can control the order in which each effect appears on the slide. Each animation effect is numbered in PowerPoint. The numbers do not appear on the actual slides during the presentation, but you can reorder the effect numbers in the Custom Animation pane to control the order of appearance.
See the previous task, "Animating a Single Slide Object," to learn more about assigning animation effects to various slide elements.