Just found this
Aperol is made with sweet and bitter oranges, but if you can’t get it, try another aperitivo like Campari or ask (nicely) at a knowledgable liquor store. Campari is pretty strong so I use less of it, but you can customize to taste. No need to use a fancy sparkling wine or Champagne; another sparkling wine will do just fine. Be sure to use plenty of ice!
2 ounces (40ml) Aperol or 1 ounce (20ml) Campari
3 to 4 ounces (60ml-90ml) Prosecco
sparkling water
orange slice
1. Fill glass* generously with ice cubes.
2. Pour in Aperol or Campari, then add Prosecco.
3. Add a splash of sparkling water and a slice of orange.