Jerry Seinfeld was known to rehearse a new act in small towns before stepping on stage in larger venues. When my wife acted and sang in community plays, they always had a dress rehearsal one or two nights before the first performance. And, as a keynote speaker, I rehearse my speeches several times before I deliver them.
Many people will mentally run through their presentation or review their notes and materials but this is not nearly as effective as actually completing a full dress rehearsal. A rehearsal can help you discover rough spots and smooth out your delivery. It can help you improve transition points. And, if you are presenting with a colleague, it help you sync yourselves and prevent fatal mistakes.
I'm not suggesting that you rehearse every single sales presentation you are required to make. However, the greater the sales opportunity or the more important the client or prospect, the more important it is to run through your entire presentation to ensure that you make your key points effectively, properly handle your materials, and nail down your timing.
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