The kitchen and the surfaces should be cool. Your ingredients should be cold - Crisco cold and water iced. They should clump into small lumps before you add the water for a flakey crust
The key to fluffy crust is to work quickly and don't overwork the dough. With a blender, 2 butter knives, or your hands (I like 2 knives), 'chop' the flour/Crisco into small clumps before adding the water
Spoon the water in one tablespoon at a time while mixing until the dough ball comes together (but not so much water that it becomes tacky). Knead it once or twice - remember not to overwork the dough, or it will become tough
When you get the dough into a rough ball, cut it in half (one slightly larger, for the bottom) wrap in clear plastic, and refrigerate for 30 minutes to an hour before rolling it out
Use the smaller ball of dough first
You should have a good size surface area to roll out the dough. A cold surface is best (marble is ideal, but wood is fine too). Lightly flour your surface and rolling pin - so the dough doesn't stick. Roll from the center out. Add more flour as necessary
The dough circle rolled out should be about 12" wide and about 1/4" thick. Gently lay into the pie tin, press gently - clip the sides with scissors - but leave about an inch of overhang (keep the excess dough)