Here is a great video about making and stretching Neapolitan pizza dough.
You can watch as the pizziolo stretched the dough and gently pulls it to get the right shape.
You do not want to use a rolling pin to form your pizza dough.
Watch the hand movements in this video which will help you get a good technique to work with the dough.
The pizza maker also reminds you to use a clean surface when you work the dough. You do not want anything on your surface. You need to make sure it is very clean.
This video shows the proper technique to work the pizza dough.