How to Draw With a Scale Ruler

Determine the actual measurements of what you would like to draw. For example, if drawing a room, you would measure the height and width. Draw a working diagram of what you're measuring and add your actual measurements to it.

Choose what scale you would like to use for your drawing. This is generally done based on the complexity of the drawing and how much space is available on paper to represent it. For example, select a half inch to represent 1 foot of actual measurement.

Locate the proper scale on your three-sided ruler and begin to draw your final diagram using the actual measurements. On a half-inch scale ruler, you'll see that every half inch represents a foot of actual measurement.

Note on the bottom left of the diagram the scale that you used for the drawing. This is critical for the person who will use your diagram and has to convert it back to actual size.