I found this slide deck from 2011 and I am surprised how relevant these ideas are five years on. I'm also happy to see that more authors from business and academia are building refreshing approaches to creativity, way more useful and evidence-based than what the old books and courses on creativity used to do (the "nine dot problem" is one example of silly creativity exercises)

1. 15 great creativity activities
(Not the nine-dot problem again!)
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

2. 1. Routine is o.k.
The very first question you need to ask yourself or your team is
“what must be left the same?”
(This will let you focus on whatreally needs to be changed)
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

3. 2. Permission
Avoid intuition, transcend deduction/induction, understand then
break the rules, do not expect inspiration, step over boundaries,
be foolish, embrace ambiguity, pick a fight, make mistakes, work
hard… give yourself and others permission!
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

4. 3. Metaphors
Grab today’s newspaper and find 3 metaphors. Most go
unnoticed, so pay attention. Then build yourself 3 metaphors
about your problem. You will know that this works when your
analogies help you reframe your problem.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

5. 4. Randomness
Use randomness to go beyond intuition and commonsense. You
may grab words at random from a newspaper and do something
interesting like use them to rephrase your problem or the
company’s vision.
Build a random list of words and use them astriggers.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

6. 5. Paradoxes
A paradox is an apparently contradictory statement that leads to
a situation which seems to defy logic or intuition. They are a great
way to twist your thinking about the problem at hand. Discuss
famous paradoxes, then find a paradoxical aspect of your
problem or company
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

7. 6. Thesaurus
Words are powerful,polysemic, have rich connections and
unexpected connotations when combined or modified. Use a
thesaurus to redefine your problem.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

8. 7. Try out ideas
Paper and pencil are great to imagine ideas, but they are terrible
liars. Leave your desk and try out your ideas: ask and observe
people, build models, run quick implementations. If you do this
right, your idea will necessarily change.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

9. 8. Say stupid things
Once in a while, warn people that the next thing you will say is
“really stupid”, then go ahead and say what you really think. This
little trick has a few effects: it removes pressure, gives you license
to say anything, disrupts commonsense, and possibly can be
analysed later for its actual merit or can be combined with other
ideas.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

10. 9. Mix
Combine half-baked* ideas, join different trains of thought*.
Bring together concepts from distant fields. If your brainstorming
session seems like a competition, end it. If it feels like a jigsaw
puzzle where the picture emerges from the contribution of
everyone, you are on the right track.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>
* Here are some metaphors for free

11. 10. Talk to strangers
Find strangers to discuss your problem: literally, people you don’t
know, or people from different fields, young children, minorities,
etc. Look for people who are willing to build analogies to their
expertise and ask them to rephrase your problem in their own
terms –listen carefully.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

12. 11. Cultivate diversity
Apply this in your team: include different profiles (sp. academic
disciplines or professions). Apply it in your life: become interested
in a wide range of things, learn languages, travel, read. Pick up a
magazine you’ve never opened and read it carefully to learn one
new thing about your problem.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

13. 12. Pursue counter-
intuition
Avoid choosing “consensus” ideas, go for the controversial or
those dismissed quickly. Pick them up andanalyse their worth: it’s
there, it’s just probably not easy to grasp.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

14. 13. Sacrifice a sacred cow
Select the most “sacred” idea around the problem or the
company. Then question it, trash it, reverse it, dismiss it. This
works when it reveals an insight about the problem. Usually
sacred beliefs made sense in the past but conditions change.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

15. 14. Never become an
expert
Experience is valuable, except when you trust it. Always question
previous experiences and never, ever, think of yourself as an
expert. Experts believe they shouldn’t learn anything, and believe
me… we are all ignorant!
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>

16. 15. Avoid creativity books
Or websites, or experts. Become creative about your own
creativity. Adapt techniques to your context, better yet invent
new ones that work for you.
Dr. Ricardo Sosa <sosa.ricardo@gmail.com>