Measuring your stairs and landing areas is quite simple. All you need is a tape measure, pencil, and piece of paper. Begin with counting the number of treads you will need. Next measure the depth of each tread to make sure they are all the same, if not, note the depth of each stair. Specifically measure from the tip of the front edge to the back of the stair where it meets the riser. Next measure the width of the stair from side to side (this will be your longest measurement).