best is to take a ferry from howrah to baghbazar. frequency every 15 minutes from 8am to 7pm
then u ll get circular railway trains every half an hour from 8am to 11am and 5pm to 8pm
u can also take shared auto to shyambazar (rs.5) frequently plying and then walk to kolkata terminal if u have no luggage. its a kilometre. u can also take a bus to kolkata terminal from shyambazar. but best is train