If you arrive in Chile the best way to get somewhere with out getting lost is to take a transfer (that is my opinion). Transfer usually cost about 8 US dollars (you have to pay it in pesos witch is about 4.000 pesos). The safest transfers are the ones that have their offices inside the airport. Once you choose a transfer you give him the direction and pay him once you arrive at the house.
If you were coming to my house you will have to tell him "Me lleva a la dirección Julio Prado 1999 esquina Colo-Colo, en Ñuñoa".
Since the airport is at the other end of the city, it usually takes about an hour to get here.