Measure the cranberry
Too much cranberry covers the other ingredients and turns the drink into a juice-led serve. The IBA measure keeps it in a supporting role. If your cranberry product is very sweet, check the lime balance by tasting.
Why a cold glass matters
Because the Cosmopolitan is served without ice, a chilled coupe or cocktail glass slows warming. Shake until properly cold and fine-strain to reduce small ice fragments on the surface.
Finish the citrus profile
Express lemon or orange peel oils over the glass to strengthen aroma. The peel does not have to remain in the drink; the aim is to support the first impression, not add a heavy garnish.