There is some options:
- You can rent car from CityBee. There is a lot CityBee cars around the city. You just take one to travel whenever you want. More about that you can read here: http://lithuaniafaq.eu/question/the-easiest-way-to-rent-a-car-in-vilnius/
- Call a taxi. But remember, it’ll be a lot cheaper if you call taxi by the phone. If you sit in taxi, who is waiting at the airport, you will pay for that additional money. Better to call a taxi and wait near the airport.
- Take a bus. To the city centre you can travel with bus number 88. It cost 1 euro and you can buy ticket from bus driver.
- Take a walk. Vilnius airport is not far away from centre and if you have free time, you can walk to the centre.