For Subway :  http://www.istanbul-ulasim.com.tr
For Public Bus :   http://www.iett.gov.tr/
For Boat :  http://www.ido.com.tr/

Istanbul has two major international airports, Atatürk Airport and Sabiha Gökçen Airport. Most long-haul flights arrive at Atatürk Airport; Europeans flights might arrive at either location, depending on the operator.

From Atatürk Airport to ITU Maslak Campus: 
Take the M1 Light Railway system from Airport station to the direction of Aksaray. At the third station (Atakoy- Sirinevler Station), transfer to the Bus Line MB34 (metrobus). At 16th Station (Mecidiyekoy Station), transfer to the M2 line from Sisli-Mecidiyekoy station in the direction of ITU Ayazaga (Haciosman). Fifth station is ITU (Istanbul Technical University) Ayazaga station. The journey will take about 70-80 minutes in total.
You can also use Havatas Shuttle Service or Havas Shuttle Service from Ataturk Airport to arrive Taksim. Daily shuttle schedule and price information can be obtained from the links below. You don't have to buy tickets in advance, you pay for it on the bus. The bus does not accept foreign currency so, make sure you have Turkish Lira with you. There are exchange-offices located at the airport. From Taksim you may transfer to the subway (metro) and it will bring you directly to ?stanbul Technical University (Ayazaga station).
http://www.havatas.com/en/
http://www.havas.net/en/shuttle-parking/istanbul-ataturk-airport/
From Sabiha Gökçen Airport to ITU Maslak Campus:
Havatas Shuttle Service and Havas Shuttle Service are available from airport to TAKSIM.  Daily shuttle schedule and price information can be obtained from the links below. You don't have to buy tickets in advance, you pay for it on the bus. The bus does not accept foreign currency so, make sure you have Turkish Lira with you. There are exchange-offices located at the airport. From Taksim you may transfer to the subway (metro) and it will bring you directly to ?stanbul Technical University(Ayazaga station). 
From Taksim (City Center) to ITU Maslak Campus: 
Take the M2 metro line from Taksim station to ITU Ayazaga station toward Haciosman direction. Eighth station is ITU (Istanbul Technical University) Ayazaga station. The travel takes about 16 minutes from Taksim station.
From Sultanahmet to ITU Maslak Campus: 
Take the T1 city tramway from Sultanahmet station towards the direction of Kabatas and get off the tramway at the stop "Kabatas" (Last station in this direction). At this stop, you will see the F1 Finikular line. Take the F1 line (this line is only one station long) to arrive "Taksim". At the "Taksim station", transfer to the M2 metro line in the direction of "ITU Ayazaga, Haciosman". Eighth station is ITU (Istanbul Technical University) Ayazaga station. The journey will take about 50 minutes in total.