I've started using a punch too after doing my first two EPPs where I cut each piece by hand. And I just cut my fabric the width of the hexie plus a bit (really scientific) in squares/rectangles and then pin on the hexie paper and trim...I do agree with Francei and the fact that 1/4 inch seam is often too small. I eyeball it and go from there. I find larger seams also give more stability to the whole project. You can always trim later if you like.
No need truly for a hexie ruler.