Press Record (red button) and slowly move the phone left, right, up, and down, while keeping it aimed straight ahead. Don't tilt the camera, don't move it forward or backward, and don't move too far; an inch in each direction should suffice. The white square should "track" your object, i.e. stay fixed on it, while leaving a trail of red dots behind. Try to evenly cover the area inside the orange circle with these dots.