When you select the Bounce category in the Animation Wizard, the third page of the wizard will display a list of animation options you can choose from, and control options to set the number of times the object should bounce off the sides of the screen and at what speed.
Click on one of the animation options in the left hand panel of the page.
Click on the Once option in the Repeats panel, to allow the object to bounce off one side of the screen before the animation stops.
Type a number in the box in the Repeats panel, to set the number of sides the object will bounce off before the animation stops.
Click on the Continuously option in the Repeats panel, to allow the object to bounce continuously off the sides of the screen without stopping.
Use the slide bar in the Speed panel to increase or decrease the speed of the animation. Move the slider left to make it slower or to the right to make it faster.
Click on the Next button to go to the final page of the Animation Wizard.
Click on the Finish button to save your changes and close the Animation Wizard.