1. Mix shortening, flour, and salt together with a fork or a pastry blender until very crumbly. Add as much water as needed to hold together a tablespoon at a time, and mix lightly with a fork.
2. Roll into ball, wrap in cellophane, and refrigerate for 30min.
3. Roll gently on a floured pastry cloth (or counter) to about an inch larger than pie plate. Fold carefully in half, lift to pie plate, and unfold. Press into pan. For a single-crust pie, trim with a small knife to about 1/2 inch beyond rim. Fold up, and pinch so edge of pie is raised from rim.
For a two-crust pie, trim bottom crust to edge of rim, fill, and top with crust about 1/2 inch larger than rim. Tuck top crust under bottom along rim. Seal with floured fork.
For less sweet pie filling add sugar to crust.