In a medium bowl combine the yeast, warm water (100-105 degrees) and sugar. If you have a mixer add this to the bowl of your mixer and let it sit for 5 minutes or until it is nice and bubbly.
Add the salt and oil and then mix. Then slowly add the flour to the mixture 1 cup at a time. Mix by hand or on low speed in your mixer for a minute or until the flour is incorporated.
Once you have a good dough ball, place it on a floured surface and knead for 10 minutes. If you have a mixer with a dough hook place it on medium speed for 10 minutes.
Place the dough on a clean surface and leave it covered with a damp cotton towel or a tea towel for an hour or so. Basically until the dough doubled in size.
Divide the dough into four separate dough balls. If you only wish to make one pizza place the extra dough balls in the refrigerator wrapped in plastic wrap.
To form the pizzas, place the dough on a well floured surface and slowly work the dough into a flat disk.
The dough will make four 12-inch pizzas, or you can use it to make two 18in pizzas.
To cook the pizza preheat the oven to 550 degrees and place the pizza on a pizza pan or on a preheated pizza stone for 10-12 minutes.
When fully cooked, the crust should be slightly golden the the cheese should be melted.