This article by The Spir.it has some great basic recipes for cocktails made with bitter spirits- Campari, Cynar, Averna, Punt y Mes, and Fernet Branca. I've copied a favorite, with Punt y Mes, below. An excellent aperitif!
2 oz rye whiskey
½ oz Punt y Mes
¼- ½ oz maraschino, to taste
Combine all ingredients in a cocktail shaker filled with ice. Stir and strain into a chilled cocktail glass.