To make the basic dough, sift the flour into a large bowl...make a well in the centre, add the salt, yeast, sugar and oil. Pour in the warm water. Bring together slowly with a knife, then as a dough starts to form, tip the contents of the bowl onto a work surface and bring it all together with your hands, incorporating all of the flour...kneading into a smooth ball for about 5 minutes...the dough should be slightly springy and elastic...soft and smooth. Use flour when needed sprinkled ovwer the surface to stop the dough sticking.
Transfer the soft smooth dough back to the bowl...cover with a tea towel, and leave in a warm room for 45 minutes...it should double in size. Knock the air back out...now, if you are going to freeze, do so now...seal in a sandwich bag, or wrap fully in cling film, and pop it in the freezer...take it out about 6 hours before you need it. If not freezing, then now the dough is ready to use.
use plenty of flour to roll it into a pizza shaped base...transfer to a pizza baking tray, then cover with your toppings of choice. Bake in the oven at 180 for about 15 minuts, ir until brown and bubbly on top.
i know this seems like a long winded explanation, but it really is easy, and a hell of a lot cheaper!