Mix together warm water, yeast and sugar in a small bowl or cup and let rise in a warm place until foamy, 10 minutes.
Combine the flour and salt in a mixing bowl and make a well in the centre. Pour in the yeast mixture and the oil. Stir with a wooden spoon until the dough pulls away from the sides, then turn out on a floured surface and knead. You may have to add more flour. Knead until the dough is smooth and only slightly sticky.
Put the dough in an oiled bowl and turn to coat with a thin layer of oil. Cover with a damp tea towel and place somewhere warm to rise. Let rise until doubled, about 1 1/2 hours.
Punch down the dough, turn it onto a floured surface and shape into a ball. Let rise another 15 minutes before stretching or rolling out the dough. You can also put the dough in the refrigerator a few hours or until needed; this will make it easier to shape.
Bake the pizzas with your favourite toppings, 20 minutes at 180 degrees C.