Greve in Chianti is easily reached from Florence and from the highways. You can download here (720 Kbyte Jpeg image) a page-sized road-map suitable to be printed and covering the way from Florence to Greve.
Once you arrive in Greve, you pass the three traffic lights, then you turn to the left on a small one-way street.
At the end of this street, turn to the right and drive for about 1 km for the windy road.
Once you have arrived at the Villa, use the second gate on your left. Ring the bell.
NB. The road is sealed: if you get to the dirt road you have gone too far