After a good brainstorming session, you might end up with tones of post-its, comments and ideas in all directions. It's not a bad thing at all. The only problem comes when you need to start making sense of all the concepts produced. And the more you achieve, the worst.
To make this problem less severe, we advise you to create some order while you ideate. You can do this in several ways.
While you generate ideas, make different piles of post-its that could help you differentiate the useful concepts and the not so good ones. Don't waste a lot of time discussing which idea should go to each pile. The best is to do this quick and fast.
Separate by categories/fields
It's an advanced way to make piles. Instead of just "yes" or "no" piles, the idea is to categorise the concepts in different ways. For example "Radical" and "Conservative". Or "Behaviours", "Actions" and "Opportunities". In this way, you can later judge each idea for its category and make sense of its context.
Summarise every 30-45 minutes
Lastly, if you are doing brainstorming rounds, try to finish each series with some conclusions. Use an idea canvas for it, or whatever method you prefer.