With the limited ingredients, it is critical that you use the best quality you can afford. It is also advisable to have your ingredients super cold (freezer). The cocktail is very flavourful with bursts of herbal tastes.
I must contradict the instructions on this one because, regardless of one's preferences for their own Martinis, if you're going to make a Nick & Nora: "Always have rhythm in your shaking...a dry martini, you always shake to waltz-time."