From the bus station at Vaclav Havel Airport Prague (Terminal 1 / Terminal 2) take a bus No. 119 direction to the terminal station Nádraží Veleslavín where you change to a direct tram No. 20 (interval every 10-20 mins) to Malostranské náměstí where you get off (duration 45 min).
Direct connection between the Florenc bus station is available between 6:45 am and 8:15 pm (interval every 15 mins): Bus line No. 194 – exit stop Valdštejnské náměstí or Malostranské náměstí (duration 18-19 mins).
Direct connection between the Main Train Station is available between 5:11 am and 11:51 pm (interval every 10-20 mins): Tram line No. 15 – exit stop Malostranské náměstí (duration 14 min).
Information about public transport in Prague is available HERE