Cut down a sheet of white cardstock to 8 x 10 inches.
Disclaimer: I am not at all into being exact. I'm giving you permission to be the same for this project. It's mostly straight, but it's not important to be rigid about your measuring and cutting!
With your zero center ruler, on the horizontal, mark a the 1" and 3" on both sides, then lightly draw out three vertical lines, as shown in the picture.
Now on the vertical, mark at the 0", 2" and 4" on both sides and draw out your horizontal lines, you should have 4 of these, see picture.