sew several strips together either using mark on machine or your 1/4 in foot. Measure from the edge of the material to seam. this should be scant 1/4 in. if not then move your needle and try again. Keep trying until you have correct measurement. Then MARK the correct position of the needle with permament marker on the machine. then you can always go back to same place. If not able to move needle then keep moving material and measuring until correct and then make that position on the machine base using tape or marker. always use the same ruler to measure due to not all rulers are created equal.