You can easily take the bus to central Gothenburg. The bus stop is located just before the entrance to Waterfront Cabins. The stop is called "Frihamnsporten".
To get to the city center, you can take the following buses:
- Bus 16
- Bus X1
These buses go to Nordstan and Brunnsparken.
To purchase a ticket, you can easily download the "Västtrafik To Go" app and buy your ticket from there. A single ticket costs 36 kronor.
You can find more information about bus schedules here.