After getting my pieces in the mail, I had to unpeel all the protective backing from all the pieces. I went with 3mm black acrylic for the slide, and 3mm clear acrylic for the cursor. You might want to use the tweezers to peel the small pieces. After unpeeling everything, take note of which side is which. They're marked in the pictures (side 1 has the C/D scale, side 2 has the A/B scale). Also, note the blank circular pieces. These are the pieces that get sandwiched between the two faces of the rule, allowing it to slide.