- 20 for 20.
For a standard 20-minute sales pitch or presentation (most presentations are not 90-minute productions like the ones at CES), I suggest rehearsing the entire presentation from start to finish at least 20 times. In the first ten rehearsals, you'll likely stop and refine message points or slides. You'll probably forget many of your best lines. That's where the next ten rehearsals come in. During the next ten practice rounds focus on vocal delivery, body language, and nailing down the material.