If you're a clever showman, you'll save the best for last, preferably as a surprise to the audience.
Steve Jobs knew this instinctively, and designed his presentations to leave the best reveal for the very end. Of course, it came to be known as the iconic "One More Thing".
The first "One More Thing" was at the 1999 Macworld in San Francisco. While introducing an update to the iMac for 1999, Jobs listed off a faster processor, a larger hard drive, and a lower starting price. Then he put the words "One more thing..." on the screen, and announced that the iMac would come in colors.
During the year and half he was at Apple before that event, he tried auditioning various ways to make that splash, to various degrees of success.
At the 1998 edition of Macworld San Francisco, he casually mentioned that Apple has returned to profitability, pretty big news at the time, with an offhand comment right at the end.
At Seybold New York in March 1998, he showed off a technology demonstration of a 400 MHz G3 PowerMac by saying he had "one last thing" to show us.
Here at Seybold San Francisco, Jobs spent most of the keynote rehashing features for Mac OS 8.5 that were already demonstrated at earlier keynotes. When he was ready to foist upon the audience a sneak peak of Adobe's new InDesign page layout system, then codenamed K2, he took an approach that thankfully was never tried again: the word "Surprise" rendered in the singularly worst font ever used in an Apple keynote.
If you're the sort of person who likes to slow down and stare at car accidents, I've grabbed an image of the offending word. To protect those with weak constitutions, I've obscured it using iOS 10's new click-to-reveal technology.