Hold up an "S" hand sort of as if you were holding a microphone. This is an awkward little sign to be using in the Deaf Community eh?
But quite often our meetings are interpreted for the "Deaf-Impaired." (That isn't a technical term folks and you probably won't find it in your Speech Pathology textbook). When doing this sign it helps to move your mouth around a bit as if saying something. People generally just mouth or partially mouth the word "microphone" when doing this sign.
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