Press the small reset button on top of the measuring roller to reset its counter to zero.
Start at the beginning point of your project with both wheels of the roller on the ground.
Walk forward while rolling the wheels on the ground. For every foot that your roll the wheels, the counter will tick off one foot.
Stop rolling the wheels on the ground once you reach the end of your project measurement. For example, If you needed the linear footage of a hallway, start at the front of the hallway and end when the wheels touch the back wall.