Follow this tutorial for the how-to!
Step 1: Measuring and Cutting
The best tool for doing about 40 of these rectangle blocks is probably a chop saw. As you can tell from the pictures, I started off using a band saw, but it was taking way too long, and the cuts, obviously, weren't wonderfully straight. Chop saw all the way.
I cut about 40 of these bad boys, then sanded them to a smooth finish.
Step 2: Drilling
I would be using a strong 1/2 inch cotton rope to hold the blocks together, but since I wanted the top of the rug to be smooth, I would need to drill into the sides of the blocks, thread the rope through these holes, for a flawless rug surface.
Since my blocks were 5 inches wide, I would drill two holes into the sides of the blocks, both at the 1 inch mark of each side. This way the staggered configuration could hold strong.
I used a drill press to make the holes, and a drill bit that was slightly larger in diameter than my rope. I made a quick jig on the drill press that would allow me to just insert a block and press down, creating a precise hole. Otherwise, I would spent hours perfectly measuring and marking where the holes should go. This saved me a bunch of time as I would be making 2 holes for 40 blocks. yikes!