It is a ten minute walk from the park to the subway station at Central Park W & 72nd St on the SW corner. Ride for 8 stops and get off at Spring St. Exit via 6th Ave & Spring St at the NW corner. It is a 5 minute walk to Bar Strega from there. Total travel time- 30 minutes.
The ceremony will have already taken place earlier that morning in private. The after-ceremony gathering in the park will have conchas, drinks, music, and blankets to spread out on. There will also be time for toasts! It will likely be hot and humid so dress accordingly!