Insert a new slide with the Chart layout.
Double click on the chart. Set Chart type to 2-D Pie.
Enter data in the Data sheet such that you have 60 slices (simulating 60 seconds). Ensure that the value of each slice is the same (say 1).
Delete the legend if present and also delete the plot area. Now click anywhere on the slide and so that you are back into PowerPoint.
Select the Chart and Click on Draw Menu, Ungroup.
PowerPoint will prompt you with the following message. "This is an imported object, not a group. If you convert it to a MS Office Drawing Object, embedded data or linked information will be lost. Do you want to convert the object?" Click on Yes.
Click on Draw Menu, Group.
Now draw another Circle (to learn to draw perfect circles, click here) slightly smaller in size. and format it as required. In the demo I have formatted this smaller circle to a Preset fill named Fire.
Now select the grouped object and the smaller circle in order to make them concentric. On the Draw Menu select Align or Distribute option and then select Align Middle. And then Once again select the Draw Menu, Align or Distribute option. This time select Align Center. Now both objects are concentric.
Select only the smaller circle and set it's order to Send to Back
Select on the grouped object. Ungroup it. While the each of the slices are selected, format the slices and set them to background colour with no lines.
Select Custom Animation from the Slide Show menu and set the animation of these selected objects to "Appear" automatically after 0 seconds.
Lastly, select Slide transition from the Slide Show menu. Uncheck Advance On Mouse Click. Check Automatically and set it to 1 (or any value depending on your requirement) seconds. Click on Apply.
Run the show. Enjoy the visual countdown. Graphic on the left shows various stages of the countdown.
