From Fiumicino :

 

With the TAMbus bus, follow the directions for the buses at the arrival terminal and you will find the TAMbus line, the ticket can be bought on board or bought online on the website www.tambus.it, the ride from Fiumicino airport to Ostiense station (Piazzale XII October) costs about 13 euros per person round trip. Departures are every 30 minutes, carefully check the times on the official website. 
With the Leonardo Express train, follow the directions from the terminal for the train, buy the ticket to Ostiense station and make sure that the train stops at Ostiense station (not all trains stop here).
In both cases, once you get off at the Ostiense station, walk for 10 minutes (800 meters) or take the 716 bus, near Eataly, up to the Ostiense/Padre Giuliani ring road.
It is possible to request a private transfer, which has a variable price based on the departure airport, the people and the time (from 40 to 70 euros each way to be paid directly to the driver.)

From Ciampino airport :

Take the 720 bus to the Laurentina metro B station, then take the metro to Garbatella, then walk for ten minutes (800 metres) or get on the first bus that passes at the beginning of the Circonvallazione Ostiense to Circonvallazione Ostiense/Padre Giuliani.