• Judgement and criticism are not allowed in initial stage of generating creative ideas.
• You want to record every idea no matter how unusual. You never know; it may just lead to other ideas which are quite workable.
• You can combine ideas and connect weaker ones with stronger ones.
• Although no idea can be seen to be too extreme for suggesting during brainstorming, this might suggest a very disorganised format, and that would be inaccurate.

When properly done, brainstorming has its own set of rules and structure. It also helps to have a skilled facilitator who is both organized and diplomatic.