Step One: First make a rectangle 720x480 and fill it solid black, next make a duplicate of this and fill it solid white. Place them side by side (use coordinates in the transform tab to get it exact). Save the whole thing as your half matte file.

White half is shown as stroked with black for illustration
purposes only. Your matte shouldn't be stroked.
Step Two: For the bar, create a rectangle 1440x480 and fill it solid black. Then create a second rectangle 10x480 and fill it solid white. Use the bring to front command to mae sure it is in front of the black rectangle (if not already). Then select both rectangles (control>A), and use the align tools too center them to each other. Save the whole thing as your bar file.

Now return to 'Animating Skies and Writing Text With Light!' tutorial.
---Mark Simpson is a leader in the Adobe After Effects COW. Would you like to know more about Mark and see other articles written by him? Click here.