you need this: shaker
I know it seems superfluous, but really, if you are going to make cocktails, especially cocktails where you are extracting flavor out of fruits and herbs, you need a shaker.
It’s a great way to chill your cocktails, without drowning them in ice and watering down the flavor.
My set, which includes moscow mule mugs, is in copper. To be honest, the metal doesn’t matter… it’s really about personal preference here.
Seriously, though… this is a piece of equipment that you should have if you are going to be making any sort of craft cocktail.