Research shows there's an ideal duration for a presentation. Exceed it at your peril.
There's a reason "Death by PowerPoint" is a well known and roundly recognized problem. Despite their occasional dullness, Word, Excel, QuickBooks, and the rest, are rarely charged with bringing users to the brink of their own demise. Sure, bad spreadsheets are annoying. But bad presentations can be ridiculously painful.
As an entrepreneur, you still probably need to make presentations regularly in order to sell your ideas or train your staff, but like dangerous weapons or flammable liquids, presentations need to be handled with care.
Among her advice is the simple but powerful truth that duration matters. Even rock star presenters (consider some of TED's most riveting speakers) are only given 20 minutes to make their case. Apparently, there's a solid scientific basis for this duration, according to Weinschenk:
20-minute presentations are an ideal amount of time. Maureen Murphy tested this idea in an experiment. She had adults attending a 60 minute presentation at work, and tested to see the difference in memory and reaction to the same talk given in one 60 minute long presentation, versus a presentation that had 20 minute segments with short breaks in between. What Dr. Murphy found was that the people enjoyed the 20-minute chunked presentations more, learned more information immediately after, and retained more information a month later.
So, for the love of your listeners, take this lesson to heart: 20 minutes is the presentation-duration sweet spot. This is true even if you have more than 20-minutes worth of material to get through, insists Weinschenk, who suggests the simple solution of thoughtfully planned breaks. "If you are presenting for more than one hour you probably have a break planned. Time the break so that it comes at one of these 20 minute time periods," she writes, and goes on to caution against the temptation to simply break your material in half:
Instead of taking one long break, take several short ones. For example, it is common for a half-day workshop to go from 9 to 11:30 or 9 to 12 with one 20-30 minute break at around 10:30. Instead of one 30 minute break, have one 15 minute break and then 3 other short 5 minute breaks.
What other golden rules of presenting do you follow?
JESSICA STILLMAN is a freelance writer based in London with interests in unconventional career paths, generational differences, and the future of work. She has blogged for CBS MoneyWatch, GigaOM, and Brazen Careerist. @EntryLevelRebel