Place a point on the coordinates (3,1). Then from the point go up 1 and to the right 3 for coordinates to your next point (6, 2). Do this again for another point at (9, 3).
Go back to the point (3,1) and do the opposite; go down 1, left 3. This gets you to (0,0). Do it again to get (-1, 3).
Now draw a straight line through all of these dots.