1. Open Illustrator
  2. Press file->new or ctrl+n
  3. Go to the for web tab
  4. Create a new 1920x1080 doccument
  5. Save doccument
  6. Ensure the current color selection is white wiith black border
  7. Select the rectangle tool
  8. Create a box that is a little smaller than the canvas
  9. Set the stroke size of the box under the properties->appearance tab to 80 pt
  10. With the 80pt line to give you an idea of size, resize the box so that its roughly 60pt away from all sides of the canvas
  11. Select the line tool
  12. While holding down shift, click and drag from the left side of the box to the right side of the box to make a line that bisects the box
  13. This line should be 80pt stroke as well
  14. Repeat the above steps to make a second line
  15. Using the sekection tool, move the lines up and down to get it so that both lines are on the edge of the middle third of the box
  16. The top edge of the top line should be right on the where the box would be divided into the top and middle thirds
  17. The bottom edge of the bottom line should be right on where the box would be divided into the bottom and middle thirds
  18. You should now have a box with two horizontal lines in it
  19. Select the line tool again
  20. Again holding down shift, create a line from the top of the box to the top line
  21. Position that line a third of the way over from the left side of the box
  22. Create one final line from the bottom of the box to the bottom line
  23. Position this line on the right side so that it makes a square with the edges of the box and the bottom line

To double check things

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Original

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Matt

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Andrew