Prague’s Ruzyne Airport is located 17km west of city central. When you reach arrivals, locate a public transport desk and buy a ticket which will cover you for both bus and metro. Take bus 119 which runs every 15 minutes, to the end of the line at Dejvicka, then continue by metro into the city. This journey should take no more than 30minutes; 20 minutes for the bus, 10 minutes for the train.
Alternatively you can take a Cedaz minibus (220 114 296, www.cedaz.cz) which is located outside arrivals. The ticket needs to be purchased from the driver which cost 90Kč; minibuses depart every 30 minutes from 5:30am to 9:30pm and the journey should take 20 minutes. You can also take a Cedaz minibus to your hotel or another address, prices start from 480Kč for one to four people; five to eight people will cost 960Kč.