No pressure: To begin with, make sure that everyone in the group feels comfortable. If you have a group of people who don't know each other very well, you could break the ice by asking each of them to reveal a little known fact about themselves, maybe a hidden talent or a past achievement.

Or give everyone a different magazine or newspaper and ask them to pull out one good idea that inspired them and share it with the group - maybe it's a clever PR-led article; or just something that stopped them in their tracks. What jumped out of the page - and why?

What's it all about? Clarify the issue you want to solve at the outset.

No idea unturned. Brainstorming should be fun. There's nothing as stifling to creative thinking as criticism.

Let the ideas come thick and fast. So what if some of them are totally ludicrous? The more ideas the better. And sometimes the ideas that everyone hates to begin with can be the best and most transformational. The evaluation can wait. (Just ask Facebook's Chris Cox how much users hated Newsfeed when it launched...)

Build not destroy. Without getting bogged down on any one idea for too long, build up rather than knock back ideas - and yes, that might include building on the most ridiculous idea. You never know where it might lead.

Eyes wide open. Encourage everyone you work with to be open to and inspired by good ideas they see around them - an unusual shop window display; a clever turn of phrase on a hoarding; an unusual building - wherever they are and however unconnected they may seem to be to your business or your challenges, something, somewhere will provide that vital spark.

Capture the moment. Make sure that all the ideas are captured for all to see and ponder on further beyond the end of the session. At Twelve we like to use a star marking system to highlight our favourite ideas and follow those that get the most votes.

Mind the gap. Think about where you are now - point A - and where you want to get to - point B. Plot those two points on a white board or flip chart. What are all the things you need to fill up the gap - and what you need to do to get them.

Contrary to what you might think. Indulge in a bit of reverse thinking. What would everyone do in your position? Now do the opposite. What can you do to make the problem worse? This is a good technique to use if there aren't any immediately identifiable solutions. You could also have a bit of fun thinking of the most inappropriate solutions to the problem...

Put it in writing. Brain-writing is an offshoot of brainstorming. Everyone writes the problem at the top of a sheet of paper, followed by three ideas to solve it. Then they pass the sheet to their neighbour to build on these ideas... they in turn pass the sheet to their neighbour to build on these ideas and so on until the sheets have been round the table and are back with their originators. Read them out one by one and vote on your favourites.

Pillage and plunder. Take a fantastic idea that has really impressed and inspired you (a new brand, news, politics, science) and try applying it to your problem.

I've got a little list. Before the session, get everyone to write down 10 ideas for tackling the problem - anything goes. Share the lists around the group by email and ask everyone to vote for their top ideas - and one of those must be absurd. The ideas with the most ticks form the basis for the brainstorm.

Delusions of grandeur. Imagine how somebody else might tackle your problem - Lady GaGa, Margaret Thatcher, Gandhi, or Mark Zuckerberg. Put yourself in someone else's shoes and see what happens.