Reveal that a levitation will be performed.[1] This will immediately get people's attention and set their expectations high. Audiences look forward to levitation as one of the most intriguing magic tricks. Notifying them that you're about to do it will have them on the edge of their seats, which is essential to successfully performing the trick.
Consider building suspense throughout the magic show, so that the audience looks forward to the levitation the entire time.
To make the event seem even more mysterious, have an assistant come out and announce that you will be levitating before you walk onto the stage or into the room.