Build a transfer buffer you can explain

A transfer buffer should cover identifiable tasks, not simply a round number added to the timetable. Start by drawing the whole change between services.

Include leaving the first vehicle, finding the next departure point and any required checks or queues. A station name can conceal a long walk between platforms or separate terminals. Use the operator's current connection guidance, and check whether the tickets form a protected connection or separate bookings with different conditions.

Name the uncertainty

Write down what could consume the margin: an unfamiliar entrance, luggage, a lift route or a service that runs infrequently. Scheduled travel time between two places does not include every step before and after it. A companion's walking pace may also change the calculation.

Choose the next workable departure if you miss the planned one and check what your ticket allows. An attractive alternative is not a fallback if boarding it requires buying another ticket you have not budgeted for. Keep the official information source available offline where possible.

Review the buffer after the journey. Record which part actually took time rather than concluding that every future transfer needs the same allowance. A useful margin is one you can explain from the route and booking conditions. It gives you options without turning the whole day into waiting for the next vehicle.