The design thinking method, therefore, relies on clearly defined steps for idea generation, ideally in interdisciplinary and diverse teams, in order to obtain the most diverse approaches possible. Equally as important as having the right process and the right people is being in the right environment.
The keyword here is visualisation and it is also vital to have the corresponding visualisation tools: Visualising the process is important insofar as cognitive processes take place in a visual way. Visual perception is anything but passive, so you could say seeing is thinking.
Post its and whiteboards are perhaps the least complicated way to bring ideas to the fore. For advanced users, however, there are also complete, space-creating furniture systems that support the whole process, such as the Design Thinking Line by System 180 or the flomo design thinking set by Westermann for multidisciplinary, self-organising teams of varying compositions and sizes.