We've planned for you this trip by BUS that will bring you from the B&B Savoia to the Colusseum, passing through the historical center of Rome.
During this 20-30 minutes journey you'll see La Fontana del Tritone (by Bernini), Piazza Colonna , Piazza Venezia with the Unknown Soldier Monument, the Roman Forum and finally the Colusseum.
Very short and cheap.
Beware of Pickpocket!
You just don't forget to keep an eye on your wallet and your bag!