Brainstorming is a method for generating ideas to solve a design problem. It usually involves a group, under the direction of a facilitator. The strength of brainstorming is the potential participants have in drawing associations between their ideas in a free-thinking environment, thereby broadening the solution space.
Four rules of brainstorming
Basically, there are four rules of doing it properly:
No judgements. This is the first rule of creativity in general, really. Don’t discard anything when you’re brainstorming.
Think freely. As I said before, no matter how crazy it is; while brainstorming, ideas are neither silly nor impossible. Allow yourself to imagine as much as you want.
Big numbers. The more ideas, the better. It obviously depends on the situation, but try to produce at least 20 solutions and then you’ll see how much it helps.
Many heads are better than one. When you’re doing it in a group, accept other people’s ideas. You all work on each other’s contributions and then these will grow.