Hauppauge to Citi Field

The last time we tried to go to a Mets game we inched around the stadium trying to get to a parking lot for about 2 hours. By the time we got there it was bottom of the 4th and they still wanted $30 for parking. We just left and went to Astoria to get ramen.

What is the most cost efficient and time efficient public transportation route to get from central Suffolk to Citi Field?