I'm creating a sleight of hand based character and have drawn a fair bit of inspiration from Penn and Teller. To further the connection, how can I trade away the ability to speak for a further bonus to sleight of hand?

Ideally this will be doable by a small sized race.

I'm creating a sleight of hand–based character and have drawn a fair bit of inspiration from Teller, of Penn and Teller. To further the connection, how can I trade away the ability to speak for a further bonus to sleight of hand?

Ideally this will be doable by a small-sized race.

I'm looking for a way that only involves strict literal interpretations of the rules.