The less you handle short-crust pastry the better it is. I find I make my best pastry when I am running late and have to throw it together in a hurry.
8 of flour to 4 oz fat (my mother always used half marge and half white fat but now that animal fat is out of favour I use all marge) Rub together with fingertips or mash with a fork until it is like breadcrumbs then add cold water a little at a time until it all holds together, stirring it with a fork. Too much water makes it hard. Let it rest for a bit, then roll it out. Roll up and down, then give it a half-turn and roll the other way, the turning it gives it a chance to relax a bit.
Here is a daring way to finish off a sweet pie - flash the finished pie very briefly under the tap, then sprinkle granulated sugar on the wet pastry and bake at once. The sugar sticks to the top crust.