Petr is such a friendly and communicable person. He gave us food when we arrived in his house, told us about schedules of a public transportation in Prague, cafes, restaurants , shops which are close from his house. And his house is located not too far from the centre of the city. Firstly you need to take a bus ( bus stop is 3-4 minutes away from the house)and get to the stop called Dejvicka (it will take around 15 minutes), then go to Mustek (around 8 minutes) by a metro . And Mustek will be close to the centre of Prague. So the way will take 30 minutes approximately totally :)