We arrived in Boston Cruise Port, walked off the ship, go left and look for the bus stop, very easy to find, right across the street. Use silver line 2 To South Station. Get off at the South Station and walk to Boston Common. Just use phone for directions, a short ten- minute walk and go to the Visitors Center. (restrooms available) They offered us a walking tour with a guide for only $25.00 pp. The tour was approx. 2 1/2 hours. It was money well spent, the guide with the park service was very knowledgeable. The last four stops of the Freedom trail are on your own. When finished with the tour we went to the old Church on our own and to a Bova's bakery to enjoy cannoli's. Then walked back to south Station to get back to the ship. The bus driver stopped right in front of the ship.
Port of Boston
We had the bus all to ourselves/tap and go payment only a few dollars

Walked to Boston Common/Park
Part of the Freedom Trail walking tour

Walking Tour
A treat after walking tour
Walk to Bova's Bakery-The Instigators Film with Matt Damon was filmed here
Then walk back to bus stop.