Mapping techniques are very flexible: you can use them on your own or in large groups. You can link ideas by how they directly relate (a concept map) or by looser associations (a mind map). You can create several maps and bring them together on a big multiple map. Then stick it on the wall where everyone can see it and let it provoke more ideas and discussion.
Read more about mind mapping from the creator of the modern approach Tony Buzan.
Here’s an illustration of how concept mapping works.
Start by listing all the concepts that relate to your project or idea. Then arrange them in a hierarchy, with the most important at the top. Draw lines to indicate if any depend on others. Don’t throw away concepts that don’t fit yet – they might indicate gaps in your understanding.
And here’s a diagram showing how you can bring several mind maps together, with careful pruning as you go, to create a multiple map. This approach comes from Carl Self and is explained in slide 32 of this presentation.