The REAL SECRET to Audio/Visual is, for you, the organizer to arrive at least 45 minutes (preferably one hour) before the beginning of the event. In this way, you will have time, without rushing, to thoroughly test microphones and your presentation in all its details to your complete satisfaction. In this way, you will have confidence that the A/V is working properly, and then you can relax and truly enjoy your event!
So there actually is no secret at all. Adhering to this point will support a relaxed and enjoyable event where a/v is working just as you would like. Not adhering to this point means you will be taking a major risk that the A/V is not what you expect.