Most of the time I roll pie crusts out on a lightly floured square of aluminum foil. When I’m through I fold the foil into a square. I then tear a semi-circle from the pointed folded end. When the foil is unfolded I have a shield for the edges of the crust. This shield is much easier to position and keep in place than strips of foil and the open center allows steam to escape and the middle of the pie to brown without the edges burning.