Tianjin has a decent metro network — nine lines cover most tourist areas. The main tourist sights are accessible via Lines 1, 2, and 3, which cross the central districts. The metro is cheap, air-conditioned, and signs are in both Chinese and English. Buy a transport card (Jiaotong Yika Tong) at any station for easier travel.
Taxis are plentiful and cheap by Western standards. Most drivers don't speak English, so it helps to have your destination written in Chinese characters. Ride-hailing apps (Didi is the dominant one) work well and many accept international payment methods.
Walking is the best way to explore the concession districts — the Italian Concession, the riverside walkway, and the Binjiang Dao shopping area are all compact enough to cover on foot. The riverbank walk between the main concession districts takes about 90 minutes at a relaxed pace.