Shanghai now has thousands of bus and tram lines, which are Shanghai’s main mode of transport.
All you need is to prepare enough coins for the bus fare and the bus station name in Chinese. Most of the tickets cost you 1 or 2 yuan so you have better prepare a bag with about 20 yuan which will be enough for one person to hang around in Shanghai for a whole day.
Try the google maps direction service eg.: People’s Square to Nanjing West Road.