Not only did I write one of these in my OU MBA Module exam (B822 Creativity, Innovation & Change), I even drew it as the essay plan for one question. Large and bold with space to annotate my six ideas into each petal and to scribble down some thoughts on the introduction and conclusion (up and down the stem).

I doodled mnemonics on the themes  around the petals.

I gave myself 5 minutes per theme and 10 minutes to get into and out of the topic.

I suppose I wrote 200 to 350 words per theme.

Pegging works. 

They may not look very pretty but anagrams, sayings and mnemonics all have their place. However, you have to fix them in your head, which includes all of the senses. 

I had to visualise a couple of my mnemonic lists (VAN BECK CLIMB)as a short walk through our house seeing hockey sticks and flippers in the porch at the front door (playfulness), a woman sitting on the stairs with a broken tennis racket (adopt a set to break sets), at the top of the landing another woman cuddling an infant (it was always there, nurture it), then a massive Damien Hirst butterfly picture on the wall (broad picture, local detail) and so on ... people in a room, riding a bicycle (oh yes!), then for key components of a 'messy' problem '[I could use a colourful swimming costume: ICUACSC) a photograph of James Mason perched on the end of springboard with a Russian looking girl called Olga Mitroff.
In both cases I used this in the exam, quoting 'Mason and Mitroff' and drawing in what I saw as I walked through the house. 

I ended up with 5 mnemonics per block, some only three letters, as in VATCC and CAPO.

VATC the caveats to using a personality inventory:

• Validation
• Acceptance
• Technical considerations
• Cost

That's 15 which a week on I still know as: POVCC, MHIVE, and MDMAP ...if you can see it these are 'point of view', 'Maldhives' and 'Mindmap'. 
These 15 key letters gave me the longer mnemonics and phrases. All of this I practiced and on the day filled a 'rough book' in 10 minutes. When it came to looking at the questions, with one exception, the fit was immediate. With the third I had to cherry pick from what I had laid out. 
It took time to embed these pegs in my cerebellum, but if you want to sit down to an exam, turn the question page and develop a knowing Mona Lisa smile this is the way to do it.