International travelers will arrive in Keflavik Airport. From there you can take a bus that will bring you to very close to Reykjavik University. From there, you can take a taxi or the Straeto bus system directly to the university.
If you choose to rent a car, it is important to know that driving in Iceland is different than most places: Road and Coastal Admin page
The weather can be windy, cold, and wet very suddenly. Dress in layers with fleece or wool underneath and a waterproof shell on top.