Dust a large, flat surface with plain flour to cut down on the dough sticking while you're working.
Flatten the dough slightly; make sure to flatten the end you plan on feeding to the pasta machine. If one side of the dough is too thick, it will not catch in the rollers of the pasta machine.
Dust the pasta machine with flour. While dusting, spin the rollers to coat them with a very thin layer of flour. Dusting will keep the dough from sticking to the machine as it is being rolled out.