This is a test of commonsense. Complete the next sentence:

How to make a rum cooler cocktail 
Fill your drinking glass about 3/4 full with ice cubes. 
Put the wedge on the glass as a garnish. 
Measure and pour the lemon/lime soda and rum into the glass.
Use a barspoon to stir the drink thoroughly. Use a knife and cut a slit in the lemon wedge.