Schernus was born in Wießen, Kreis Heydekrug, now Vyžiai, Lithuania.
He was a Kapellmeister at the Stadttheater Bremerhaven, then assistant for the NDR Sinfonieorchester and at the Hamburgische Staatsoper.
[1] In 1962, Schernus moved to the Westdeutscher Rundfunk (WDR) in Cologne.
He focused on collaboration with contemporary composers whose works he prepared and conducted.
[1] Under his direction, numerous world premieres have been performed, which have established and consolidated the reputation of the Kölner Rundfunkchor nationally and internationally.