Group size: Just yourself; yourself and one other person; up to 6 or so in a group.
Simply because you don’t know it all. Also, the “green light” (open to anything) gives permission to think “outside the box” and come up with new ideas (and/or derive feasible ideas from some of the unfeasible, way-out ideas that are allowed and encouraged in the green light portion!).
Who to include
People who will be the most helpful, as this is not a social nicety or bonding type of thing (though bonding will occur!). If you’re a metaphysical or intellectual type, then include people who are results-getters. If you’re a results-getter, then include other results-getters but also a few metaphysical or intellectual type (or even eccentrics). The objective is to get new ideas and to go beyond normal restricted thinking.
A side effect is that the participants will tend to “enroll” in your cause and are likely to support it with funds or advice or efforts.
What to do
Green light it: Tell everyone this is “green light” with no negatives, no stops. No suggestion would be addressed as not being something possible. (Later, after the “green light” portion, you can see what is not feasible and then prioritize.)
Let others talk most of the time: Don’t spend time talking, as you’re there for their ideas, not to be right or to look good by coming up with ideas or excuses, etc. Spend as little time as possible explaining the basic problem, passion, and other specifics. Others should do 80%, at least, of the talking, with you asking questions.
Take notes!: Be sure to write notes – shows respect, that you are taking it seriously
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