[header] How to make martinis [title] Add the ice, gin, and vermouth to a cocktail shaker and stir well. [step] To make the martini, you'll need a cocktail shaker or mixing glass. Fill it with cracked ice , 2 ½ ounces (74 ml) of gin and ½ ounce (15 ml) of dry vermouth. 
Use a long spoon to stir the ingredients for about 15 seconds or until it's well mixed. [substeps] If you prefer, you can shake the martini to mix it together.