the directions from the airport are quite simply you have two choises the first you can take the blu line of metro and you go directly to keramikos station which is 5 minutes walking. If you want you can take also a taxi aporximately 40 euro. From the port you can take the train you will reach at montastiraki station then you will change lines, you have to take the metro (the blu line) with final destination keramikos. then you have to walk 5 minutes.  

Distances
Alkmini Theatre 0,1 klm
Benaki Museum 0,3 klm
Gazi Technopolis 0,4 klm
Keramikos Archaeological Site 0,6 klm
National Observatory 0,7 klm
Filopappos Hill 1,1 klm
Roman Market 1,1 klm
Attalos Arcade 1,2 klm
Ermou Street (Greatest Market of the City) 1,3 klm
Monastiraki Square 1,3 klm
Acropolis and Acropolis Museum 1,7 klm
Odeon of Herodes Atticus 1,7 klm