Flights into the YYJ Victoria Airport are optimal with rental car services close by. The airport is about 20 mins from Victoria.
Here are a few helpful link to plan your trip
Bus service from the airport and to the ferries make a cost efficient way to move around Victoria.
Alternatively flights into Vancouver or Abbotsford are sometimes cheaper but please remember that you have to make arrangements to take the Ferry across to the island.
Ferry travel should be booked ahead of time. For prices and sailing times check out the attached website.