Public transit (cheapest / can be slow if you must make transfers)
Taxi (fastest & easiest if you have much luggage / drivers overcharging)
Hotel sponsored van/private car to/from airport (upscale hotels)
Rental car (flexibility / limited & expensive parking, maze-like streets)
Caveat emptor: Prague's taxis have earned a notorious reputation for dishonesty in overcharging tourists. Know the law: A taxi ride to/from the airport to/from the center is legally set at 500 Czech crowns. All taxis have digital meters in them, but the meters can supposedly be altered to run higher. Most Czechs negotiate a price, lower than what the official metered price would be, with the driver before beginning their journey. (this includes to/from the airport.)
Many Prague residents prefer using AAA Radiotaxi service, as the drivers and meters are supposed to be honest, but the metered price is non-negotiable.
Step 2: Find a transit station
Step 3: Find a transit route to your destination
Use Prague Transit's Journey Planner if you need help finding the best way to your destination.
Step 4: Get your ticket
Ticket types shown (left to right):
Discounted youth ticket (You must have a Prague metro ID card also!)
30-minute full fare ticket
90-minute full fare ticket
1-day unlimited ride pass
3-day unlimited ride pass
It's easiest and often cheaper to buy one of the unlimited ride passes if you plan to be in Prague for a few days. (No additional ticket is needed for luggage if you have one of these.) These passes can be bought at the airport, train/bus stations at the time of your arrival to Prague.
Last step: Validate your ticket
During your ride
Beware of pickpockets!
Obvious tourists are quickly targeted. Do the following:
Be alert to suspicious behavior
Avoid close contact with strangers where possible
Do not let others separate you from your group
Men: Keep wallet in a tightly closed front pocket
Women: Keep purse shut and close in front of you
Backpacks: Take off back and hold or set in front of you
If you feel a thieving hand, yell ZLO DJAY (thief in Czech) as loud as you can. Make a scene! Pickpockets fear attention.