First we select the text tool it looks like a big T and create a box. You can use the options to the right to change fonts, styles,and the size of your text. Show in the first picture
After your done that make a line from the middle of the screen to the top of the screen. then add up to two frames at the top. Create a key frame, then make another line that starts in the middle of the screen but drag the other end of it beside the first line so its a triangle. add the same amount of frames as before. This time when you add another key frame just drag the second line more to the right with the black cursor tool it should look like the second picture repeat this until you have a full rotation.
This isn't essential but it make it look good. You should try to stop the full rotation at 30 or 60 frames depending on the format. This will make each rotation a full second long
Lastly, select all the frames you've done so far and paste them into the next space however many times you want it to repeat then select the number and change it in each frame(A LOT easier then remaking it everytime)
Now you have a awesome movie countdown!!