I was unsure at first what weight I would need, as it needs to be able to stand up on its own a bit. Thankfully in the shop we could touch and feel plenty of examples, and ended up with this simple, ever so slightly striped orange, and a gentle minty green with satin type finish.
Then came the first joy of cutting everything to size. I used the very simple cutting board I have, and did it sheet by sheet. It is meant to be able take several sheets at once, but I wouldn't take the risk. To make things easier, I only measured once on the base card. That happened luckily to match one of the lines on the board. From then on I just put every sheet of white card against that line. Then this is what I did for all the rest: each layer of the matting is one square smaller as on my cutting board than the one before. I needed 50 'large' ones of each colour (one square less than the white base), and 50 'smaller' ones (a square less again). That way instead of measuring anything all I had to do was line up aainst a particular line on the cutting board. Since for the easle everything is square anyway, it worked in all directions.
It was a bit labour intensive, but I managed to do all this sat back in the recliner chair, with my craft mat and cutting board on my lap and a table next to me.
You'll notice the strips of coloured paper that were left over. I kept them to make paper chains.