Arriving by plane at Schiphol (Amsterdam)
Website of Schiphol Airport: https://www.schiphol.nl/en/
Arriving by plane at Rotterdam-The Hague airport
website of Rotterdam-The Hague airport: https://www.rotterdamthehagueairport.nl/en/
Arriving by (high-speed) train
website of the Dutch Railways (NS): https://www.ns.nl/en
for international travel information: https://www.nsinternational.nl/en
Arriving by car
Delft can be reached by the highways A13 and A4, running in between Rotterdam and The Hague. At the A13 take exit #10 'Delft-Zuid' and follow the indications to TU Delft. At the A4 take exit # 14 'Delft' and follow the N470 road until the indications of TU Delft and follow them. Parking around Delft University is free of charge, however it might take some time before you find a parking space. Please do not park outside official parking spaces as this might lead to fines.
Arriving and going around by (electric) bike
Delft has excellent biking paths that lead you through the nicest surroundings and spots, in and around the center. (Remember that The Netherlands is totally flat) While in Delft, you might think of renting a bike. By bike you can easily go in 45 minutes to Rotterdam or The Hague as well.
Places where you could rent a bike: https://www.wijtman.nl/fietsen-huren-in-delft-en-vlaardingen