Mix yeast, sugar and water, and allow to activate. Add oil, then salt and flour, kneading to a soft dough. Allow to rise for 30 minutes to an hour. Punch down and knead. Roll out to desired size, usually in two pieces. Place on grill to cook one side, turn over and top the pizza. Return to grill to cook the toppings. (Grill should not be too excessively hot.)