1. Drive to manhattan, and park on 61st or 62nd near 1st avenue. Parking is easy after 7.
2. Take the tram to Roosevelt Island. It picks up from the foot of the Queensboro Bridge at 1st and 59. It costs a metrocard swipe.
3. There is a Starbucks on the Island, I think it used to close at like 9. Then, you can walk on the boardwalk along the east river, and sit on the benches there. Bring sweaters if it will be chilly.