You will need some hard card paper that is white in colour, a steel or wooden scale with markings in centimetres and inches, a protractor or what we call a D, a cutter or fine scissors, a sharp pencil and a fine pointed pen. You can also keep an eraser and a sharpener handy. You can use paper as well but hard card paper is easier to use once it's made. The ruler or scale we will be making will be able to measure six inches on one side and fifteen centimetres on the other. Draw a straight line using the ruler and pencil on the card paper that measures six and a half inches which is approximately sixteen and a half centimetres. Use the protractor to mark ninety degrees from the edges of the straight line and draw a pair of lines one and a half inch wide each. Connect the ends of these lines. You will now have a rectangle that measures 6.5" × 1.5 inches. Cut this out with the scissors or cutter. Use a scale to mark the centimetre scale on one side and inches on the other.