Applause expresses appreciation or approval. In hearing Western culture, they typically clap with the palms of their hands. Sound-oriented.
In American Deaf culture, as visually-oriented, Deaf people ususally wave their hands in the air. This Deaf applause (waving in the air) began in the 1980s. To this day, it has been widely prevalent. In general, it's practiced in Deaf space as well as ASL classes.
In some settings, some Deaf people would sometimes do both clapping with palms and waving hands alternatively like wave-hands, clap-hands, wave-hands, clap-hands. This can be said half-jokedly as 'bilingual'.
Demo by Gary Sue Etkie (April 2017).
Clapping in the air above head can be done by some. Or, some may wave hands in the air and then clap hands also in the air alternatively.
These variations are creative. But, in most cases, it's waving hands.