How do you serve spritzes to a crowd? Batch the base, not the bubbles, with a jug planner

Ingredient	Measure
Bitter orange aperitivo (Aperol or similar)	60 ml (2 oz)
Prosecco or other dry sparkling wine	90 ml (3 oz)
Soda water	30 ml (1 oz)
Ice	Fill the glass
Garnish	Orange slice

Built in a large wine glass, on ice. The IBA lists 90 ml Prosecco and 60 ml Aperol with a splash of soda; the popular 3-2-1 version gives the soda a full 30 ml.