How to do it
Start with a blank slide, and follow these steps:
1. Set the slide background to black.
2. Create a rectangle at the left hand side of the slide, with a height equivalent to the entire height of the slide and a width about one tenth of the width of the whole slide.
3. Format this rectangle by setting the outline to no outline, and the fill to a gradient fill in red, with a vertical pattern so it is lighter in the middle and darker at the edges.
4. Set the entrance animation effect for this shape to Fly In, Set Start to After Previous, Property to from left, and speed to medium.
5. Copy this shape.
6. Paste, and move the resulting shape to the right extreme of the slide to form a symmetrical matching shape on the other side of the slide. By now it should look like this
7. Edit the animation properties of this second shape so that the Property is From Right, and the start is With Previous.
8. Repeat the Paste, and place the pasted shape next to the first one on the left hand side. Retain the existing animation settings.
9. Repeat this process alternating adding shapes to the left and right hand sides in turn (the order is critical) ensuring that all the left hand shapes have Start parameters of After Previous, and Property settings of From Left and those on the right of With Previous and From Right, until you have filled the screen.
10. Finally you may like to add a message such as “That’s all folks!" (another homage to classic cinema). This should have animation settings of Appear and After Previous.
The final result should look like this