You’ll spot buses in various colours. The municipality IETT ones are red, white or green. To use them buy an InstanbulKard card or a ticket at major bus stops and shops before boarding. A single journey costs around 1,95 TL. If a bus crosses the Bosphorus or Fatih Sultan Mehmed Bridge you need two tickets.
Private buses are blue or green. Tickets are the same price as IETT buses, and you can pay using your IstanbulKart. Remember that you cannot pay for your journey after boarding the bus. Buy an IstanbulKart if you plan to take busses to travel.
Minibuses also run from central minibus stations for 14 to 15 people. Another alternative is the Dolmus. A type of yellow taxi for up to 8. It won’t leave until all 8 seats are occupied.