By public transport, you can take the tram 23 (stop Noorderhelling), the bus to Somerland or the train to Rotterdam Stadion
The island is car-free, but you can park your car on Cor Kieboomplein or on the Hoendiep and walk to the island
If you’re feeling fancy, the water taxi will take you too. Stop at 010 Stadion Feyenoord.